diff --git a/src/main/java/ui/window/JDialogAvatarModelChecker.java b/src/main/java/ui/window/JDialogAvatarModelChecker.java
index 0b78621a843f3023cd80dfcc95e2932c95f092b0..609b25baf477a3457301ac043eb814fcee326dd9 100644
--- a/src/main/java/ui/window/JDialogAvatarModelChecker.java
+++ b/src/main/java/ui/window/JDialogAvatarModelChecker.java
@@ -729,7 +729,7 @@ public class JDialogAvatarModelChecker extends javax.swing.JFrame implements Act
             timer.scheduleAtFixedRate(mcm, 0, 500);
 
             // Setting options
-            amc.setCompressionFactor(1);
+            amc.setCompressionFactor(2);
             amc.setIgnoreEmptyTransitions(ignoreEmptyTransitionsSelected);
             amc.setIgnoreConcurrenceBetweenInternalActions(ignoreConcurrenceBetweenInternalActionsSelected);
             amc.setIgnoreInternalStates(ignoreInternalStatesSelected);
diff --git a/ttool/src/test/java/avatartranslator/AvatarExpressionTest.java b/ttool/src/test/java/avatartranslator/AvatarExpressionTest.java
index 88c068afd1f461082cb9d2365a50ff0f7efc5864..d49c5a5a0e1678b6c434c0bbf089a51c93255910 100644
--- a/ttool/src/test/java/avatartranslator/AvatarExpressionTest.java
+++ b/ttool/src/test/java/avatartranslator/AvatarExpressionTest.java
@@ -194,6 +194,20 @@ public class AvatarExpressionTest {
         assertTrue(e1.getResult(ss) == 17);
         assertTrue(e2.getResult(ss) == 1);
         assertTrue(e3.getResult(ss) == 0);
+        
+        as.setAttributeOptRatio(4);
+        ss = new SpecificationState();
+        ss.setInit(as, false);
+        
+        e1 = new AvatarExpressionSolver("block1.x + block2.y");
+        assertTrue(e1.buildExpression(as));
+        e2 = new AvatarExpressionSolver("-block1.x / block1.y - 15 * block2.z + 1 == -46");
+        assertTrue(e2.buildExpression(as));
+        e3 = new AvatarExpressionSolver("not(-block2.x / block2.z - not(block1.x + block2.y) * -2 + -(1) <= -(-4 + 7))");
+        assertFalse(e3.buildExpression(as));
+        assertTrue(e1.getResult(ss) == 17);
+        assertTrue(e2.getResult(ss) == 1);
+        assertTrue(e3.getResult(ss) == 0);
     }
 
 }