diff --git a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/ZipGenerator.java b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/ZipGenerator.java
index e5a8a25eb..ce63c59be 100644
--- a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/ZipGenerator.java
+++ b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/ZipGenerator.java
@@ -121,19 +121,23 @@ public class ZipGenerator {
 		File f = new CSFile(actualDir);
 
 		String files[] = f.list();
-		for (int i = 0; i < files.length; i++) {
-			if ( new CSFile(actualDir + files[i]).isFile() && ((ext == null || files[i].endsWith(ext)) && (noExt == null || !files[i].endsWith(noExt)))) {
-				FileInputStream fi = new FileInputStream(actualDir + files[i]);
-				BufferedInputStream origin = new BufferedInputStream(fi, BUFFER);
-				ZipEntry entry = new ZipEntry(statedDir + files[i]);
-				names.add(statedDir + files[i]);
-				out.putNextEntry(entry);
-				int count;
-				while ((count = origin.read(data, 0, BUFFER)) != -1) {
-					out.write(data, 0, count);
-				}
-				origin.close();
-			}
+		if (files == null) {
+      System.out.println("no files found in "+f.getName());
+		} else {
+		  for (int i = 0; i < files.length; i++) {
+		    if ( new CSFile(actualDir + files[i]).isFile() && ((ext == null || files[i].endsWith(ext)) && (noExt == null || !files[i].endsWith(noExt)))) {
+		      FileInputStream fi = new FileInputStream(actualDir + files[i]);
+		      BufferedInputStream origin = new BufferedInputStream(fi, BUFFER);
+		      ZipEntry entry = new ZipEntry(statedDir + files[i]);
+		      names.add(statedDir + files[i]);
+		      out.putNextEntry(entry);
+		      int count;
+		      while ((count = origin.read(data, 0, BUFFER)) != -1) {
+		        out.write(data, 0, count);
+		      }
+		      origin.close();
+		    }
+		  }
 		}
 	}
 
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 03e40d5c6..3edd09a85 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
@@ -510,7 +510,7 @@ public class I18nConstants {
   public static final String TYPE_SPECIFIC_CHECKS_DT_CANONICAL_TYPE = "TYPE_SPECIFIC_CHECKS_DT_CANONICAL_TYPE";
   public static final String TYPE_SPECIFIC_CHECKS_DT_CANONICAL_RESOLVE = "TYPE_SPECIFIC_CHECKS_DT_CANONICAL_RESOLVE";
   public static final String TYPE_SPECIFIC_CHECKS_DT_UUID_STRAT = "Type_Specific_Checks_DT_UUID_Strat";
-  public static final String TYPE_SPECIFIC_CHECKS_DT_UUID_VAID = "Type_Specific_Checks_DT_UUID_Vaid";
+  public static final String TYPE_SPECIFIC_CHECKS_DT_UUID_VALID = "Type_Specific_Checks_DT_UUID_Valid";
   public static final String UNABLE_TO_CONNECT_TO_TERMINOLOGY_SERVER = "Unable_to_connect_to_terminology_server";
   public static final String UNABLE_TO_CONNECT_TO_TERMINOLOGY_SERVER_USE_PARAMETER_TX_NA_TUN_RUN_WITHOUT_USING_TERMINOLOGY_SERVICES_TO_VALIDATE_LOINC_SNOMED_ICDX_ETC_ERROR__ = "Unable_to_connect_to_terminology_server_Use_parameter_tx_na_tun_run_without_using_terminology_services_to_validate_LOINC_SNOMED_ICDX_etc_Error__";
   public static final String UNABLE_TO_FIND_BASE_DEFINITION_FOR_LOGICAL_MODEL__FROM_ = "Unable_to_find_base_definition_for_logical_model__from_";
diff --git a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/xhtml/HierarchicalTableGenerator.java b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/xhtml/HierarchicalTableGenerator.java
index b197b484b..4c07394f5 100644
--- a/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/xhtml/HierarchicalTableGenerator.java
+++ b/org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/xhtml/HierarchicalTableGenerator.java
@@ -598,7 +598,7 @@ public class HierarchicalTableGenerator extends TranslatingUtilities {
     TableModel model = new TableModel(id, isActive);
     
     model.setAlternating(alternating);
-    model.setDocoImg(prefix+"help16.png");
+    model.setDocoImg(Utilities.pathURL(prefix, "help16.png"));
     model.setDocoRef(Utilities.pathURL(prefix, "formats.html#table"));
     model.getTitles().add(new Title(null, model.getDocoRef(), translate("sd.head", "Name"), translate("sd.hint", "The logical name of the element"), null, 0));
     model.getTitles().add(new Title(null, model.getDocoRef(), translate("sd.head", "Flags"), translate("sd.hint", "Information about the use of the element"), null, 0));
@@ -615,7 +615,7 @@ public class HierarchicalTableGenerator extends TranslatingUtilities {
     TableModel model = new TableModel(id, true);
     
     model.setAlternating(true);
-    model.setDocoImg(prefix+"help16.png");
+    model.setDocoImg(Utilities.pathURL(prefix, "help16.png"));
     model.setDocoRef(Utilities.pathURL(prefix, "formats.html#table"));    
     model.getTitles().add(new Title(null, model.getDocoRef(), translate("sd.head", "Name"), translate("sd.hint", "The logical name of the element"), null, 0));
     model.getTitles().add(new Title(null, model.getDocoRef(), translate("sd.head", "L Flags"), translate("sd.hint", "Information about the use of the element - Left Structure"), null, 0).setStyle("border-left: 1px grey solid"));
diff --git a/org.hl7.fhir.utilities/src/main/resources/Messages.properties b/org.hl7.fhir.utilities/src/main/resources/Messages.properties
index edcc34f0b..39d7fee92 100644
--- a/org.hl7.fhir.utilities/src/main/resources/Messages.properties
+++ b/org.hl7.fhir.utilities/src/main/resources/Messages.properties
@@ -208,7 +208,7 @@ Type_Specific_Checks_DT_URI_UUID = URI values cannot start with uuid:
 Type_Specific_Checks_DT_URI_WS = URI values cannot have whitespace(''{0}'')
 Type_Specific_Checks_DT_URL_Resolve = URL value ''{0}'' does not resolve
 Type_Specific_Checks_DT_UUID_Strat = UUIDs must start with urn:uuid:
-Type_Specific_Checks_DT_UUID_Vaid = UUIDs must be valid
+Type_Specific_Checks_DT_UUID_Valid = UUIDs must be valid (and lowercase)
 Validation_BUNDLE_Message = The first entry in a message must be a MessageHeader
 Validation_VAL_Content_Unknown = Unrecognised Content {0}
 Validation_VAL_NoType = Unknown type {0}
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 c289d1a66..f44803446 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
@@ -2035,7 +2035,7 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
       }
 
       if (url != null && url.startsWith("urn:uuid:")) {
-        rule(errors, IssueType.INVALID, e.line(), e.col(), path, Utilities.isValidUUID(url.substring(9)), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_UUID_VAID);
+        rule(errors, IssueType.INVALID, e.line(), e.col(), path, Utilities.isValidUUID(url.substring(9)), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_UUID_VALID);
       }
       if (url != null && url.startsWith("urn:oid:")) {
         rule(errors, IssueType.INVALID, e.line(), e.col(), path, Utilities.isOid(url.substring(8)), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_OID_VALID);