diff --git a/src/AasxCsharpLibrary/AdminShellPackageEnv.cs b/src/AasxCsharpLibrary/AdminShellPackageEnv.cs
index 3f02303a..1d726e98 100644
--- a/src/AasxCsharpLibrary/AdminShellPackageEnv.cs
+++ b/src/AasxCsharpLibrary/AdminShellPackageEnv.cs
@@ -1090,7 +1090,8 @@ public void TemporarilySaveCloseAndReOpenPackage(
                 {
                     _openPackage = Package.Open(Filename, FileMode.OpenOrCreate);
 
-                }            }
+                }            
+            }
         }
 
         private int BackupIndex = 0;
diff --git a/src/AasxCsharpLibrary/Extensions/ExtendBlob.cs b/src/AasxCsharpLibrary/Extensions/ExtendBlob.cs
index 1812b97d..d8ee065e 100644
--- a/src/AasxCsharpLibrary/Extensions/ExtendBlob.cs
+++ b/src/AasxCsharpLibrary/Extensions/ExtendBlob.cs
@@ -29,7 +29,10 @@ public static Blob ConvertFromV10(this Blob blob, AasxCompatibilityModels.AdminS
         public static Blob ConvertFromV20(this Blob blob, AasxCompatibilityModels.AdminShellV20.Blob sourceBlob)
         {
             blob.ContentType = sourceBlob.mimeType;
-            blob.Value = Encoding.ASCII.GetBytes(sourceBlob.value);
+            if (!string.IsNullOrEmpty(sourceBlob.value))
+            {
+                blob.Value = Encoding.ASCII.GetBytes(sourceBlob.value);
+            }            
             return blob;
         }
 
diff --git a/src/AasxCsharpLibrary/Extensions/ExtendConceptDescription.cs b/src/AasxCsharpLibrary/Extensions/ExtendConceptDescription.cs
index 1cdae0f4..7bb64c7e 100644
--- a/src/AasxCsharpLibrary/Extensions/ExtendConceptDescription.cs
+++ b/src/AasxCsharpLibrary/Extensions/ExtendConceptDescription.cs
@@ -260,13 +260,19 @@ public static ConceptDescription ConvertFromV20(
 
             if (srcCD.IsCaseOf != null && srcCD.IsCaseOf.Count != 0)
             {
-                if (cd.IsCaseOf == null)
-                {
-                    cd.IsCaseOf = new List<IReference>();
-                }
                 foreach (var caseOf in srcCD.IsCaseOf)
                 {
-                    cd.IsCaseOf.Add(ExtensionsUtil.ConvertReferenceFromV20(caseOf, ReferenceTypes.ModelReference));
+                    IReference newCaseOf = null;
+                    if(caseOf != null && !caseOf.IsEmpty)
+                    {
+                        newCaseOf = ExtensionsUtil.ConvertReferenceFromV20(caseOf, ReferenceTypes.ModelReference);
+                    }
+
+                    if(newCaseOf != null)
+                    {
+                        cd.IsCaseOf ??= new List<IReference>();
+                        cd.IsCaseOf.Add(newCaseOf);
+                    }
                 }
             }
 
diff --git a/src/AasxCsharpLibrary/Extensions/ExtendEmbeddedDataSpecification.cs b/src/AasxCsharpLibrary/Extensions/ExtendEmbeddedDataSpecification.cs
index 1f72ab79..f914e75f 100644
--- a/src/AasxCsharpLibrary/Extensions/ExtendEmbeddedDataSpecification.cs
+++ b/src/AasxCsharpLibrary/Extensions/ExtendEmbeddedDataSpecification.cs
@@ -49,31 +49,38 @@ public static EmbeddedDataSpecification ConvertFromV20(this EmbeddedDataSpecific
         {
             if (sourceEmbeddedSpec != null)
             {
-                embeddedDataSpecification.DataSpecification = ExtensionsUtil.ConvertReferenceFromV20(sourceEmbeddedSpec.dataSpecification, ReferenceTypes.ExternalReference);
+                if (sourceEmbeddedSpec.dataSpecification != null)
+                {
+                    embeddedDataSpecification.DataSpecification = ExtensionsUtil.ConvertReferenceFromV20(sourceEmbeddedSpec.dataSpecification, ReferenceTypes.ExternalReference);
 
-                // TODO (MIHO, 2022-19-12): check again, see questions
-                var oldid = new[] {
+                    // TODO (MIHO, 2022-19-12): check again, see questions
+                    var oldid = new[] {
                     "http://admin-shell.io/DataSpecificationTemplates/DataSpecificationIEC61360/2/0",
                     "http://admin-shell.io/DataSpecificationTemplates/DataSpecificationIEC61360",
                     "www.admin-shell.io/DataSpecificationTemplates/DataSpecificationIEC61360"
-                };
-                var newid = "http://admin-shell.io/DataSpecificationTemplates/DataSpecificationIEC61360/3/0";
+                    };
+                    var newid = "http://admin-shell.io/DataSpecificationTemplates/DataSpecificationIEC61360/3/0";
 
-                // map all "usable" old ids to new one ..
-                foreach (var oi in oldid)
-                    if (sourceEmbeddedSpec.dataSpecification?.Matches("", false, "IRI", oi,
-                        AasxCompatibilityModels.AdminShellV20.Key.MatchMode.Identification) == true)
-                    {
-                        embeddedDataSpecification.DataSpecification.Keys[0].Value = newid;
-                    }
-            }
+                    // map all "usable" old ids to new one ..
+                    foreach (var oi in oldid)
+                        if (sourceEmbeddedSpec.dataSpecification?.Matches("", false, "IRI", oi,
+                            AasxCompatibilityModels.AdminShellV20.Key.MatchMode.Identification) == true)
+                        {
+                            embeddedDataSpecification.DataSpecification.Keys[0].Value = newid;
+                        } 
+                }
 
-            if (sourceEmbeddedSpec.dataSpecificationContent?.dataSpecificationIEC61360 != null)
-            {
-                embeddedDataSpecification.DataSpecificationContent =
-                    new DataSpecificationIec61360(null).ConvertFromV20(
-                        sourceEmbeddedSpec.dataSpecificationContent.dataSpecificationIEC61360);
+                if (sourceEmbeddedSpec.dataSpecificationContent != null)
+                {
+                    if (sourceEmbeddedSpec.dataSpecificationContent?.dataSpecificationIEC61360 != null)
+                    {
+                        embeddedDataSpecification.DataSpecificationContent =
+                            new DataSpecificationIec61360(null).ConvertFromV20(
+                                sourceEmbeddedSpec.dataSpecificationContent.dataSpecificationIEC61360);
+                    } 
+                }
             }
+            
             return embeddedDataSpecification;
         }
 
diff --git a/src/AasxCsharpLibrary/Extensions/ExtendISubmodelElement.cs b/src/AasxCsharpLibrary/Extensions/ExtendISubmodelElement.cs
index 9c4d2f85..1d8e9fa3 100644
--- a/src/AasxCsharpLibrary/Extensions/ExtendISubmodelElement.cs
+++ b/src/AasxCsharpLibrary/Extensions/ExtendISubmodelElement.cs
@@ -557,16 +557,15 @@ private static void BasicConversionFromV20(this ISubmodelElement submodelElement
 
             if (sourceSubmodelElement.hasDataSpecification != null && sourceSubmodelElement.hasDataSpecification.Count > 0)
             {
-                //TODO (jtikekar, 0000-00-00): EmbeddedDataSpecification?? (as per old implementation)
-                submodelElement.EmbeddedDataSpecifications ??= new List<IEmbeddedDataSpecification>();
-
-                //TODO (jtikekar, 0000-00-00): DataSpecificationContent?? (as per old implementation)
-                foreach (var sourceDataSpec in sourceSubmodelElement.hasDataSpecification)
+                foreach (var sourceEmbeddedDataSpec in sourceSubmodelElement.hasDataSpecification)
                 {
-                    submodelElement.EmbeddedDataSpecifications.Add(
-                        new EmbeddedDataSpecification(
-                            ExtensionsUtil.ConvertReferenceFromV20(sourceDataSpec.dataSpecification, ReferenceTypes.ExternalReference),
-                            null));
+                    var newEmbeddedDataSpec = new EmbeddedDataSpecification (null, null);
+                    newEmbeddedDataSpec.ConvertFromV20(sourceEmbeddedDataSpec);
+                    if(newEmbeddedDataSpec.DataSpecification != null || newEmbeddedDataSpec.DataSpecificationContent != null)
+                    {
+                        submodelElement.EmbeddedDataSpecifications ??= new List<IEmbeddedDataSpecification>();
+                        submodelElement.EmbeddedDataSpecifications.Add(newEmbeddedDataSpec);
+                    }
                 }
             }