diff --git a/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.jena-wrapper-for-sadl/src/main/java/com/ge/research/sadl/jena/translator/JenaTranslatorPlugin.java b/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.jena-wrapper-for-sadl/src/main/java/com/ge/research/sadl/jena/translator/JenaTranslatorPlugin.java
index b1f1dd923..7ace2f580 100644
--- a/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.jena-wrapper-for-sadl/src/main/java/com/ge/research/sadl/jena/translator/JenaTranslatorPlugin.java
+++ b/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.jena-wrapper-for-sadl/src/main/java/com/ge/research/sadl/jena/translator/JenaTranslatorPlugin.java
@@ -1272,7 +1272,7 @@ else if (ftype.equals(BuiltinType.Assign)) {
 			Builtin bltin = BuiltinRegistry.theRegistry.getImplementation(builtinName);
 			if (bltin == null) {
 				logger.error("Something went wrong finding/loading Builtin '" + builtinName + "'");
-				addError("Unable to resolve built-in '" + builtinName + "'");
+				addError("Unable to resolve built-in '" + builtinName + "' in rule '" + getRuleInTranslation().getRuleName() + "'");
 			}
 			else {
 				String uri = bltin.getURI();
@@ -1466,11 +1466,14 @@ else if (ITranslator.isKnownNode(node)) {
 			return "?" + getNewVariableForRule();
 		}
 		else if (node == null) {
-			throw new TranslationException("Encountered null node in nodeToString; this indicates incorrect intermediate form and should not happen");
+//			throw new TranslationException("Encountered null node in nodeToString; this indicates incorrect intermediate form and should not happen");
+			addError(new ModelError("Encountered null node in nodeToString; this indicates incorrect intermediate form and should not happen", ErrorType.ERROR));
 		}
 		else {
-			throw new TranslationException("Nnode '" + node.toString() + "' cannot be translated to Jena format.");
+//			throw new TranslationException("Nnode '" + node.toString() + "' cannot be translated to Jena format.");
+			addError(new ModelError("Nnode '" + node.toString() + "' cannot be translated to Jena format.", ErrorType.ERROR));
 		}
+		return "<null>";
 	}
 
 	private Literal constantToLiteral(ConstantNode node) throws TranslationException {
diff --git a/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.jena/src/com/ge/research/sadl/jena/JenaBasedSadlModelProcessor.java b/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.jena/src/com/ge/research/sadl/jena/JenaBasedSadlModelProcessor.java
index 0bb8fcad6..52bdfe29a 100644
--- a/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.jena/src/com/ge/research/sadl/jena/JenaBasedSadlModelProcessor.java
+++ b/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.jena/src/com/ge/research/sadl/jena/JenaBasedSadlModelProcessor.java
@@ -7664,6 +7664,17 @@ public Object processExpression(PropOfSubject expr)
         boolean specialCntIdxProcessing = false;
         boolean lIsConstantExpression = false;
         
+        boolean predicateIsNegatedType = false;
+        if (predicate instanceof UnaryExpression && 
+        		((UnaryExpression)predicate).getOp().contentEquals("not") &&
+        		((UnaryExpression)predicate).getExpr() instanceof Constant &&
+        		((Constant)((UnaryExpression)predicate).getExpr()).getConstant().equals("a type")) {
+        	// negated
+        	predicateIsNegatedType = true;
+        	predicate = ((UnaryExpression)predicate).getExpr();
+        }
+        
+        	
 		if (predicate instanceof Constant) {
 			// this is a pseudo PropOfSubject; the predicate is a constant
 			lIsConstantExpression = true;
@@ -7733,7 +7744,11 @@ public Object processExpression(PropOfSubject expr)
 				trPred = new NamedNode(RDFS.subClassOf.getURI());  // new RDFTypeNode();
 				((NamedNode)trPred).setContext(predicate);
 				((NamedNode)trPred).setNodeType(NodeType.ObjectProperty);
-				return new TripleElement((Node)null, (Node)trPred, (Node)trSubj);
+				TripleElement tr = new TripleElement((Node)null, (Node)trPred, (Node)trSubj);
+				if (predicateIsNegatedType) {
+					tr.setType(TripleModifierType.Not);
+				}
+				return tr;
 			} else if (cnstval.equals("value") && getTarget() instanceof Query) {
 				// this is to be a delayed evaluation: don't use the expression as the query but evaluate
 				// the expression at runtime and use the value as the query
diff --git a/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.swi-prolog-plugin/src/main/java/com/ge/research/sadl/swi_prolog_plugin/Activator.java b/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.swi-prolog-plugin/src/main/java/com/ge/research/sadl/swi_prolog_plugin/Activator.java
deleted file mode 100644
index fbb7cff79..000000000
--- a/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.swi-prolog-plugin/src/main/java/com/ge/research/sadl/swi_prolog_plugin/Activator.java
+++ /dev/null
@@ -1,30 +0,0 @@
-package com.ge.research.sadl.swi_prolog_plugin;
-
-import org.osgi.framework.BundleActivator;
-import org.osgi.framework.BundleContext;
-
-public class Activator implements BundleActivator {
-
-	private static BundleContext context;
-
-	static BundleContext getContext() {
-		return context;
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.osgi.framework.BundleActivator#start(org.osgi.framework.BundleContext)
-	 */
-	public void start(BundleContext bundleContext) throws Exception {
-		Activator.context = bundleContext;
-	}
-
-	/*
-	 * (non-Javadoc)
-	 * @see org.osgi.framework.BundleActivator#stop(org.osgi.framework.BundleContext)
-	 */
-	public void stop(BundleContext bundleContext) throws Exception {
-		Activator.context = null;
-	}
-
-}
diff --git a/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.swi_prolog.feature/feature.xml b/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.swi_prolog.feature/feature.xml
index fb0bbac87..f2ed0b294 100644
--- a/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.swi_prolog.feature/feature.xml
+++ b/sadl3/com.ge.research.sadl.parent/com.ge.research.sadl.swi_prolog.feature/feature.xml
@@ -6,7 +6,8 @@
       provider-name="GE Global Research">
 
    <description url="http://www.example.com/description">
-      The SADL Prlog Plug-in is a Prolog-based reasoner for the Semantic Application Design Language (SADL), which is a controlled
+      The SADL Prolog Plug-in is a Prolog-based reasoner for the Semantic
+Application Design Language (SADL), which is a controlled
 English grammar and Eclipse IDE for building, testing, and deploying
 semantic models.
    </description>