Index: Ringtoets/Common/src/Ringtoets.Common.IO/ReferenceLineMetaImporter.cs
===================================================================
diff -u -rdd5ae117c10d97b388757d9d2a865c0860a64448 -r239ea628125c5ec4004a843abce2d269af93c431
--- Ringtoets/Common/src/Ringtoets.Common.IO/ReferenceLineMetaImporter.cs	(.../ReferenceLineMetaImporter.cs)	(revision dd5ae117c10d97b388757d9d2a865c0860a64448)
+++ Ringtoets/Common/src/Ringtoets.Common.IO/ReferenceLineMetaImporter.cs	(.../ReferenceLineMetaImporter.cs)	(revision 239ea628125c5ec4004a843abce2d269af93c431)
@@ -66,11 +66,7 @@
         /// Reads and validates the <see cref="ReferenceLineMeta"/> objects from the shape file.
         /// </summary>
         /// <returns>The read <see cref="ReferenceLineMeta"/> objects.</returns>
-        /// <exception cref="CriticalFileReadException">Thrown when:
-        /// <list type="bullet">
-        /// <item>The shape file does not contain poly lines.</item>
-        /// <item>The shape file contains multiple poly lines.</item>
-        /// </list></exception>
+        /// <exception cref="CriticalFileReadException">Thrown when the shape file does not contain poly lines.</exception>
         /// <exception cref="CriticalFileValidationException">Thrown when:
         /// <list type="bullet">
         /// <item>The shape file does not contain the required attributes.</item>
Index: Ringtoets/Common/src/Ringtoets.Common.IO/ReferenceLinesMetaReader.cs
===================================================================
diff -u -rdd5ae117c10d97b388757d9d2a865c0860a64448 -r239ea628125c5ec4004a843abce2d269af93c431
--- Ringtoets/Common/src/Ringtoets.Common.IO/ReferenceLinesMetaReader.cs	(.../ReferenceLinesMetaReader.cs)	(revision dd5ae117c10d97b388757d9d2a865c0860a64448)
+++ Ringtoets/Common/src/Ringtoets.Common.IO/ReferenceLinesMetaReader.cs	(.../ReferenceLinesMetaReader.cs)	(revision 239ea628125c5ec4004a843abce2d269af93c431)
@@ -57,7 +57,6 @@
         /// <item>The shape file does not contain the mandatory attributes.</item>
         /// <item>Has an empty <see cref="assessmentsectionIdAttributeKey"/> attribute.</item>
         /// <item>The shape file has non-line geometries in it.</item>
-        /// <item>Contains multiple poly lines.</item>
         /// </list></exception>
         public static List<ReferenceLineMeta> ReadReferenceLinesMetas(string shapeFilePath)
         {
@@ -177,16 +176,13 @@
         /// </summary>
         /// <param name="lineData">The <see cref="MapFeature"/> to create a <see cref="ReferenceLineMeta"/> from.</param>
         /// <returns>The newly created <see cref="ReferenceLineMeta"/>.</returns>
-        /// <exception cref="CriticalFileReadException">Thrown when the shape file contains multiple poly lines.</exception>
         private static ReferenceLineMeta CreateReferenceLineMeta(MapLineData lineData)
         {
-            var features = lineData.Features.ToArray();
+            var feature = lineData.Features.First();
 
-            var feature = features[0];
-
             string assessmentSectionId = GetAssessmentSectionId(feature);
-            int? signalingValue = GetSignalingValueAttributeKey(feature);
-            int? lowerLimitValue = GetLowerLimitValueAttribute(feature);
+            int? signalingValue = ParseNormValue(feature.MetaData[signalingValueAttributeKey]);
+            int? lowerLimitValue = ParseNormValue(feature.MetaData[lowerLimitValueAttributeKey]);
             IEnumerable<Point2D> geometryPoints = GetSectionGeometry(feature);
 
             var referenceLineMeta = new ReferenceLineMeta
@@ -211,13 +207,12 @@
         /// </summary>
         /// <param name="lineFeature">The <see cref="MapFeature"/> to get the geometry from.</param>
         /// <returns>A <see cref="Point2D"/> collection that represents the <paramref name="lineFeature"/>'s geometry.</returns>
-        /// <exception cref="CriticalFileReadException">Thrown when the shape file contains multiple poly lines.</exception>
         private static IEnumerable<Point2D> GetSectionGeometry(MapFeature lineFeature)
         {
             var mapGeometries = lineFeature.MapGeometries.ToArray();
             if (mapGeometries.Length > 1)
             {
-                throw new CriticalFileReadException(RingtoetsCommonIOResources.ReferenceLineReader_File_contains_unsupported_multi_polyline);
+                return Enumerable.Empty<Point2D>();
             }
 
             return mapGeometries[0].PointCollections.First().Select(p => new Point2D(p.X, p.Y));
@@ -228,14 +223,20 @@
             return Convert.ToString(lineFeature.MetaData[assessmentsectionIdAttributeKey]);
         }
 
-        private static int? GetSignalingValueAttributeKey(MapFeature lineFeature)
+        private static int? ParseNormValue(object readObject)
         {
-            return lineFeature.MetaData[signalingValueAttributeKey] as int?;
+            try
+            {
+                return Convert.ToInt32(readObject);
+            }
+            catch (Exception exception)
+            {
+                if (exception is InvalidCastException || exception is FormatException || exception is OverflowException)
+                {
+                    return null;
+                }
+                throw;
+            }
         }
-
-        private static int? GetLowerLimitValueAttribute(MapFeature lineFeature)
-        {
-            return lineFeature.MetaData[lowerLimitValueAttributeKey] as int?;
-        }
     }
 }
\ No newline at end of file
Index: Ringtoets/Common/test/Ringtoets.Common.IO.Test/ReferenceLinesMetaReaderTest.cs
===================================================================
diff -u -r1307b18d38ccc588650530e11f000925f0484163 -r239ea628125c5ec4004a843abce2d269af93c431
--- Ringtoets/Common/test/Ringtoets.Common.IO.Test/ReferenceLinesMetaReaderTest.cs	(.../ReferenceLinesMetaReaderTest.cs)	(revision 1307b18d38ccc588650530e11f000925f0484163)
+++ Ringtoets/Common/test/Ringtoets.Common.IO.Test/ReferenceLinesMetaReaderTest.cs	(.../ReferenceLinesMetaReaderTest.cs)	(revision 239ea628125c5ec4004a843abce2d269af93c431)
@@ -122,18 +122,18 @@
 
         [Test]
         [TestCase("NBPW_MultiPolyLines.shp")]
-        public void ReadReferenceLinesMeta_ShapefileHasMultiplePolylines_ThrowCriticalFileReadException(string shapeFileName)
+        public void ReadReferenceLinesMeta_ShapefileHasMultiplePolylines_ReturnsEmptyReferenceLines(string shapeFileName)
         {
             // Setup
             string invalidFilePath = Path.Combine(testDataPath, shapeFileName);
 
             // Call
-            TestDelegate call = () => ReferenceLinesMetaReader.ReadReferenceLinesMetas(invalidFilePath);
+            var referenceLineMetas = ReferenceLinesMetaReader.ReadReferenceLinesMetas(invalidFilePath);
 
             // Assert
-            var expectedMessage = "Het bestand bevat een multi-polylijn. Multi-polylijnen worden niet ondersteund.";
-            var message = Assert.Throws<CriticalFileReadException>(call).Message;
-            Assert.AreEqual(expectedMessage, message);
+            Assert.AreEqual(2, referenceLineMetas.Count);
+            CollectionAssert.IsEmpty(referenceLineMetas[0].ReferenceLine.Points);
+            CollectionAssert.IsEmpty(referenceLineMetas[1].ReferenceLine.Points);
         }
 
         [Test]
Index: Ringtoets/Integration/src/Ringtoets.Integration.Forms/Commands/AssessmentSectionFromFileCommandHandler.cs
===================================================================
diff -u -r37235d0863116292cc4b095dcf2d19cf6d14c6b2 -r239ea628125c5ec4004a843abce2d269af93c431
--- Ringtoets/Integration/src/Ringtoets.Integration.Forms/Commands/AssessmentSectionFromFileCommandHandler.cs	(.../AssessmentSectionFromFileCommandHandler.cs)	(revision 37235d0863116292cc4b095dcf2d19cf6d14c6b2)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Forms/Commands/AssessmentSectionFromFileCommandHandler.cs	(.../AssessmentSectionFromFileCommandHandler.cs)	(revision 239ea628125c5ec4004a843abce2d269af93c431)
@@ -19,6 +19,7 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Windows.Forms;
@@ -103,9 +104,21 @@
             assessmentSection.Id = selectedItem.AssessmentSectionId;
             assessmentSection.ReferenceLine = selectedItem.ReferenceLine;
 
+            if (!assessmentSection.ReferenceLine.Points.Any())
+            {
+                log.Warn(Resources.AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_Importing_ReferenceLineFailed);
+            }
+
             if (selectedLimitValue.HasValue)
             {
-                assessmentSection.FailureMechanismContribution.Norm = selectedLimitValue.Value;
+                try
+                {
+                    assessmentSection.FailureMechanismContribution.Norm = selectedLimitValue.Value;
+                }
+                catch (ArgumentOutOfRangeException exception)
+                {
+                    log.Warn(string.Format(Resources.AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_Unable_to_set_value_0, selectedLimitValue.Value), exception);
+                }
             }
             return assessmentSection;
         }
@@ -148,7 +161,7 @@
         private void ValidateReferenceLineMetas(string folderpath)
         {
             var importer = new ReferenceLineMetaImporter(folderpath);
-            referenceLineMetas = importer.GetReferenceLineMetas().ToArray();
+            referenceLineMetas = importer.GetReferenceLineMetas();
 
             if (!referenceLineMetas.Any())
             {
Index: Ringtoets/Integration/src/Ringtoets.Integration.Forms/Properties/Resources.Designer.cs
===================================================================
diff -u -r7729d796720c55da3ba99916c98c2be0a9d7ca40 -r239ea628125c5ec4004a843abce2d269af93c431
--- Ringtoets/Integration/src/Ringtoets.Integration.Forms/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 7729d796720c55da3ba99916c98c2be0a9d7ca40)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Forms/Properties/Resources.Designer.cs	(.../Resources.Designer.cs)	(revision 239ea628125c5ec4004a843abce2d269af93c431)
@@ -116,6 +116,16 @@
         }
         
         /// <summary>
+        ///   Looks up a localized string similar to Het importeren van de referentielijn is mislukt..
+        /// </summary>
+        public static string AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_Importing_ReferenceLineFailed {
+            get {
+                return ResourceManager.GetString("AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_Importing_Referen" +
+                        "ceLineFailed", resourceCulture);
+            }
+        }
+        
+        /// <summary>
         ///   Looks up a localized string similar to Er zijn geen instellingen gevonden voor het geselecteerde traject. Standaardinstellingen zullen gebruikt worden..
         /// </summary>
         public static string AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_No_settings_found_for_AssessmentSection {
@@ -126,6 +136,16 @@
         }
         
         /// <summary>
+        ///   Looks up a localized string similar to De waarde &apos;{0}&apos; kan niet gezet..
+        /// </summary>
+        public static string AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_Unable_to_set_value_0 {
+            get {
+                return ResourceManager.GetString("AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_Unable_to_set_val" +
+                        "ue_0", resourceCulture);
+            }
+        }
+        
+        /// <summary>
         ///   Looks up a localized string similar to Er kunnen geen trajecten gelezen worden uit het shape bestand..
         /// </summary>
         public static string AssessmentSectionFromFileCommandHandler_ValidateReferenceLineMetas_No_referenceLines_in_file {
Index: Ringtoets/Integration/src/Ringtoets.Integration.Forms/Properties/Resources.resx
===================================================================
diff -u -r7729d796720c55da3ba99916c98c2be0a9d7ca40 -r239ea628125c5ec4004a843abce2d269af93c431
--- Ringtoets/Integration/src/Ringtoets.Integration.Forms/Properties/Resources.resx	(.../Resources.resx)	(revision 7729d796720c55da3ba99916c98c2be0a9d7ca40)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Forms/Properties/Resources.resx	(.../Resources.resx)	(revision 239ea628125c5ec4004a843abce2d269af93c431)
@@ -275,4 +275,10 @@
   <data name="AssessmentSectionFromFileCommandHandler_ValidateReferenceLineMetas_No_referenceLines_in_file" xml:space="preserve">
     <value>Er kunnen geen trajecten gelezen worden uit het shape bestand.</value>
   </data>
+  <data name="AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_Importing_ReferenceLineFailed" xml:space="preserve">
+    <value>Het importeren van de referentielijn is mislukt.</value>
+  </data>
+  <data name="AssessmentSectionFromFileCommandHandler_CreateAssessmentSection_Unable_to_set_value_0" xml:space="preserve">
+    <value>De waarde '{0}' kan niet gezet.</value>
+  </data>
 </root>
\ No newline at end of file
Index: Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/RingtoetsPluginTest.cs
===================================================================
diff -u -r0b6cce0bd86288273634f7ead3817885a7c20fd0 -r239ea628125c5ec4004a843abce2d269af93c431
--- Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/RingtoetsPluginTest.cs	(.../RingtoetsPluginTest.cs)	(revision 0b6cce0bd86288273634f7ead3817885a7c20fd0)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Plugin.Test/RingtoetsPluginTest.cs	(.../RingtoetsPluginTest.cs)	(revision 239ea628125c5ec4004a843abce2d269af93c431)
@@ -34,7 +34,6 @@
 using Core.Common.Gui;
 using Core.Common.Gui.ContextMenu;
 using Core.Common.Gui.Forms.MainWindow;
-using Core.Common.Gui.Forms.ViewHost;
 using Core.Common.Gui.Plugin;
 using Core.Common.Gui.Settings;
 using Core.Common.TestUtil;
@@ -683,8 +682,8 @@
 
                 DialogBoxHandler = (name, wnd) =>
                 {
-                    var selectionDialog = (ReferenceLineMetaSelectionDialog)new FormTester(name).TheObject;
-                    var grid = (DataGridViewControl)new ControlTester("ReferenceLineMetaDataGridViewControl", selectionDialog).TheObject;
+                    var selectionDialog = (ReferenceLineMetaSelectionDialog) new FormTester(name).TheObject;
+                    var grid = (DataGridViewControl) new ControlTester("ReferenceLineMetaDataGridViewControl", selectionDialog).TheObject;
                     var dataGridView = grid.Controls.OfType<DataGridView>().First();
                     dataGridView[0, 0].Selected = true;
                     new ButtonTester("Ok", selectionDialog).Click();