diff --git a/library/fhir2/fhir2_factory.pas b/library/fhir2/fhir2_factory.pas
index bfc3eb553..fe2fd3f34 100644
--- a/library/fhir2/fhir2_factory.pas
+++ b/library/fhir2/fhir2_factory.pas
@@ -184,7 +184,7 @@ function TFHIRFactoryR2.buildOperationOutcome(i18n: TI18nSupport; langList: THTT
     finally
       iss.free;
     end;
-    op.link;
+    result := op.link;
   finally
     op.free;
   end;
diff --git a/library/fhir3/fhir3_factory.pas b/library/fhir3/fhir3_factory.pas
index d74bea402..6fbbf61cf 100644
--- a/library/fhir3/fhir3_factory.pas
+++ b/library/fhir3/fhir3_factory.pas
@@ -184,7 +184,7 @@ function TFHIRFactoryR3.buildOperationOutcome(i18n: TI18nSupport; langList: THTT
     finally
       iss.free;
     end;
-    op.link;
+    result := op.link;
   finally
     op.free;
   end;
diff --git a/library/fhir4b/fhir4b_factory.pas b/library/fhir4b/fhir4b_factory.pas
index 0dd18c883..f38ddabb3 100644
--- a/library/fhir4b/fhir4b_factory.pas
+++ b/library/fhir4b/fhir4b_factory.pas
@@ -185,7 +185,7 @@ function TFHIRFactoryR4B.buildOperationOutcome(i18n: TI18nSupport; langList: THT
     finally
       iss.free;
     end;
-    op.link;
+    result := op.link;
   finally
     op.free;
   end;
diff --git a/library/fhir5/fhir5_factory.pas b/library/fhir5/fhir5_factory.pas
index 9a51f52db..8e2dc2eaf 100644
--- a/library/fhir5/fhir5_factory.pas
+++ b/library/fhir5/fhir5_factory.pas
@@ -185,7 +185,7 @@ function TFHIRFactoryR5.buildOperationOutcome(i18n: TI18nSupport; langList: THTT
     finally
       iss.free;
     end;
-    op.link;
+    result := op.link;
   finally
     op.free;
   end;
diff --git a/library/fsl/fsl_base.pas b/library/fsl/fsl_base.pas
index 5a31827bc..1c5f1f6c3 100644
--- a/library/fsl/fsl_base.pas
+++ b/library/fsl/fsl_base.pas
@@ -1019,7 +1019,7 @@ procedure handleObjectTrackingFail(msg : String);
   f : System.text;
 begin
   // Application is pretty much cactus at this point, so we don't mind doing
-  // slow file operation inside such a system critical lock as GLock
+  // a slow file operation inside such a system critical lock as GLock
 
   try
     fn := 'c:\temp\object-tracking-errors.log';
diff --git a/library/ftx/fhir_codesystem_service.pas b/library/ftx/fhir_codesystem_service.pas
index edb0bc240..0754ec6bc 100644
--- a/library/ftx/fhir_codesystem_service.pas
+++ b/library/ftx/fhir_codesystem_service.pas
@@ -329,6 +329,7 @@ constructor TFHIRCodeSystemEntry.Create(res : TFHIRResourceProxyV);
 begin
   inherited Create;
   FCodeSystemProxy := res;
+  FLoadingState := cseNotLoaded;
 end;
 
 constructor TFHIRCodeSystemEntry.Create(res: TFHIRCodeSystemW);
@@ -336,7 +337,7 @@ constructor TFHIRCodeSystemEntry.Create(res: TFHIRCodeSystemW);
   inherited Create;
   FCodeSystem := res;
   LoadCodeSystem;
-  FLoadingState := cseNotLoaded;
+  FLoadingState := cseLoaded;
 end;
 
 destructor TFHIRCodeSystemEntry.Destroy;
@@ -451,7 +452,8 @@ procedure TFHIRCodeSystemEntry.SetCodeSystem(const Value: TFHIRCodeSystemW);
 begin
   FCodeSystem.free;
   FCodeSystem := value;
-  LoadCodeSystem;
+  if FCodeSystem <> nil then
+    LoadCodeSystem;
 end;
 
 function TFHIRCodeSystemEntry.GetUrl: String;
diff --git a/library/ftx/fhir_valuesets.pas b/library/ftx/fhir_valuesets.pas
index 13b0efb92..263f06f68 100644
--- a/library/ftx/fhir_valuesets.pas
+++ b/library/ftx/fhir_valuesets.pas
@@ -3226,7 +3226,7 @@ function TFHIRValueSetExpander.processCode(cs : TCodeSystemProvider; parent : TF
       exit;
 
 
-    if (cs.expandLimitation > 0) then
+    if (cs <> nil) and (cs.expandLimitation > 0) then
     begin
       cnt := FCSCounter[cs.systemUri];
       if (cnt = nil) then
@@ -3345,7 +3345,7 @@ function TFHIRValueSetExpander.processCode(cs : TCodeSystemProvider; parent : TF
               end;
             end;
           end
-          else if csProps <> nil then
+          else if (csProps <> nil) and (cs <> nil) then
           begin
             for cp in csprops do
             begin