diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index e69de29bb..071feb145 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -0,0 +1,3 @@
+* fix R2B for checking resource IDs
+* Properly check code validity when an expansion is provided, but the code system is unknown
+* fix problem with R2B StructureDefinition transform 
diff --git a/org.hl7.fhir.convertors/pom.xml b/org.hl7.fhir.convertors/pom.xml
index 150b899e1..add0690bd 100644
--- a/org.hl7.fhir.convertors/pom.xml
+++ b/org.hl7.fhir.convertors/pom.xml
@@ -73,6 +73,19 @@
             <optional>true</optional>
         </dependency>
 
+        <!-- HTTP Client -->
+        <dependency>
+          <groupId>org.apache.httpcomponents</groupId>
+          <artifactId>httpclient</artifactId>
+          <optional>true</optional>
+        </dependency>
+        <dependency>
+          <groupId>com.squareup.okhttp3</groupId>
+          <artifactId>okhttp</artifactId>
+          <version>4.9.0</version>
+          <optional>true</optional>
+        </dependency>
+
         <!-- JUnit Jupiter -->
         <dependency>
             <groupId>org.junit.jupiter</groupId>
diff --git a/org.hl7.fhir.convertors/src/main/java/org/hl7/fhir/convertors/conv14_50/StructureDefinition14_50.java b/org.hl7.fhir.convertors/src/main/java/org/hl7/fhir/convertors/conv14_50/StructureDefinition14_50.java
index c714327c1..a789c1190 100644
--- a/org.hl7.fhir.convertors/src/main/java/org/hl7/fhir/convertors/conv14_50/StructureDefinition14_50.java
+++ b/org.hl7.fhir.convertors/src/main/java/org/hl7/fhir/convertors/conv14_50/StructureDefinition14_50.java
@@ -177,7 +177,9 @@ public class StructureDefinition14_50 {
         if (src.hasDifferential()) {
             if (src.hasDifferential())
                 tgt.setDifferential(convertStructureDefinitionDifferentialComponent(src.getDifferential()));
-            tgt.getDifferential().getElementFirstRep().getType().clear();
+            if (!tgt.getDifferential().getElementFirstRep().getPath().contains(".")) {
+              tgt.getDifferential().getElementFirstRep().getType().clear();
+            }
         }
         if (tgt.getDerivation() == TypeDerivationRule.SPECIALIZATION) {
             for (ElementDefinition ed : tgt.getSnapshot().getElement()) {
diff --git a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/terminologies/ValueSetCheckerSimple.java b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/terminologies/ValueSetCheckerSimple.java
index 81695a771..fa446b133 100644
--- a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/terminologies/ValueSetCheckerSimple.java
+++ b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/terminologies/ValueSetCheckerSimple.java
@@ -149,7 +149,11 @@ public class ValueSetCheckerSimple implements ValueSetChecker {
       if (cs == null) {
         warningMessage = "Unable to resolve system "+system;
         if (!inExpansion) {
-          throw new FHIRException(warningMessage);
+          if (valueset.hasExpansion()) {
+            return new ValidationResult(IssueSeverity.ERROR, context.formatMessage(I18nConstants.CODESYSTEM_CS_UNK_EXPANSION, valueset.getUrl(), code.getCode().toString(), code.getSystem()));
+          } else {
+            throw new FHIRException(warningMessage);
+          }
         }
       }
       if (cs != null && cs.hasSupplements()) {
diff --git a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/i18n/I18nConstants.java b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/i18n/I18nConstants.java
index 3eb7c0bd4..475b1b510 100644
--- a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/i18n/I18nConstants.java
+++ b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/i18n/I18nConstants.java
@@ -53,6 +53,7 @@ public class I18nConstants {
   public static final String CODESYSTEM_CS_NO_SUPPLEMENT = "CODESYSTEM_CS_NO_SUPPLEMENT"; 
   public static final String CODESYSTEM_CS_SUPP_CANT_CHECK = "CODESYSTEM_CS_SUPP_CANT_CHECK";
   public static final String CODESYSTEM_CS_SUPP_INVALID_CODE = "CODESYSTEM_CS_SUPP_INVALID_CODE";
+  public static final String CODESYSTEM_CS_UNK_EXPANSION = "CODESYSTEM_CS_UNK_EXPANSION";
   public static final String CODE_FOUND_IN_EXPANSION_HOWEVER_ = "Code_found_in_expansion_however_";
   public static final String CODING_HAS_NO_SYSTEM__CANNOT_VALIDATE = "Coding_has_no_system__cannot_validate";
   public static final String CONTAINED_RESOURCE_DOES_NOT_APPEAR_TO_BE_A_FHIR_RESOURCE_UNKNOWN_NAME_ = "Contained_resource_does_not_appear_to_be_a_FHIR_resource_unknown_name_";
diff --git a/org.hl7.fhir.utilities/src/main/resources/Messages.properties b/org.hl7.fhir.utilities/src/main/resources/Messages.properties
index 50b380871..20281b53d 100644
--- a/org.hl7.fhir.utilities/src/main/resources/Messages.properties
+++ b/org.hl7.fhir.utilities/src/main/resources/Messages.properties
@@ -641,3 +641,4 @@ CODESYSTEM_CS_SUPP_CANT_CHECK = CodeSystem {0} cannot be found, so can't check i
 CODESYSTEM_CS_SUPP_INVALID_CODE = The code ''{1}'' is not declared in the base CodeSystem {0} so is not valid in the supplement
 SD_VALUE_TYPE_IILEGAL = The element {0} has a {1} of type {2}, which is not in the list of allowed types ({3})
 SD_NO_TYPES_OR_CONTENTREF = The element {0} has no assigned types, and no content reference
+CODESYSTEM_CS_UNK_EXPANSION = The code provided ({2}) is not in the value set {0}, and a code is required from this value set. The system {1} is unknown.
diff --git a/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java b/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java
index cc3fd0233..506704856 100644
--- a/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java
+++ b/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java
@@ -2002,7 +2002,7 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
     }
     if (type.equals(ID)) {
       // work around an old issue with ElementDefinition.id
-      if (!context.getPath().equals("ElementDefinition.id") && !VersionUtilities.versionsCompatible("1.4", this.context.getVersion())) {
+      if (!context.getPath().equals("ElementDefinition.id") || VersionUtilities.versionsCompatible("1.4", this.context.getVersion())) {
         rule(errors, IssueType.INVALID, e.line(), e.col(), path, FormatUtilities.isValidId(e.primitiveValue()), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_ID_VALID, e.primitiveValue());
       }
     }
@@ -4330,7 +4330,7 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
     }
     if (ei.definition != null) {
       if (debug) {
-        System.out.println(Utilities.padLeft("", ' ', stack.depth())+ "Check "+ei.getPath()+" against defn "+ei.definition.getId());
+        System.out.println(Utilities.padLeft("", ' ', stack.depth())+ "Check "+ei.getPath()+" against defn "+ei.definition.getId()+" from "+profile.getUrl());
       }
       checkChildByDefinition(hostContext, errors, profile, definition, resource, element, actualType, stack, inCodeableConcept, checkDisplayInContext, ei, extensionUrl, ei.definition, false);
     }