diff --git a/plugins/com.minres.scviewer.database.ftr/src/com/minres/scviewer/database/ftr/FtrDbLoader.java b/plugins/com.minres.scviewer.database.ftr/src/com/minres/scviewer/database/ftr/FtrDbLoader.java
index d5f8990..37bfb58 100644
--- a/plugins/com.minres.scviewer.database.ftr/src/com/minres/scviewer/database/ftr/FtrDbLoader.java
+++ b/plugins/com.minres.scviewer.database.ftr/src/com/minres/scviewer/database/ftr/FtrDbLoader.java
@@ -328,7 +328,6 @@ public class FtrDbLoader implements IWaveformDbLoader {
 				long array_len = readArrayLength();
 				assert(array_len==-1);
 				CborType next = peekType();
-				int chunk_idx=0;
 				while(next != null && !break_type.isEqualType(next)) {
 					long tag = readTag();
 					switch((int)tag) {
@@ -400,7 +399,6 @@ public class FtrDbLoader implements IWaveformDbLoader {
 					}
 					}
 					next = peekType();
-					chunk_idx++;
 				}
 			} catch(IOException e) {
 				long pos = 0;
@@ -468,7 +466,6 @@ public class FtrDbLoader implements IWaveformDbLoader {
 				long tx_size = cborDecoder.readArrayLength();
 				long txId = 0;
 				long genId = 0;
-				long attr_idx=0;
 				for(long i = 0; i<tx_size; ++i) {
 					long tag = cborDecoder.readTag();
 					switch((int)tag) {
@@ -497,10 +494,8 @@ public class FtrDbLoader implements IWaveformDbLoader {
 					default:  { // skip over 7:begin attr, 8:record attr, 9:end attr
 						long sz = cborDecoder.readArrayLength();
 						assert(sz==3);
-						long name_id = cborDecoder.readInt();
-						String name = loader.strDict.get((int)name_id);
-						long type_id = cborDecoder.readInt();
-						switch((int)type_id) {
+						cborDecoder.readInt();
+						switch((int)cborDecoder.readInt()) {
 						case 0: // BOOLEAN
 							cborDecoder.readBoolean();
 							break;
@@ -512,7 +507,6 @@ public class FtrDbLoader implements IWaveformDbLoader {
 						default:
 							cborDecoder.readInt();
 						}
-						attr_idx++;
 					}
 					}
 				}
diff --git a/plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/RulerPainter.java b/plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/RulerPainter.java
index d3c7a1e..725033c 100644
--- a/plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/RulerPainter.java
+++ b/plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/RulerPainter.java
@@ -56,8 +56,9 @@ public class RulerPainter implements IPainter {
         int baselineY=waveCanvas.rulerHeight - 1;
         int bottom=waveCanvas.rulerHeight - 2;
 
+        long safe_scale_factor = scaleFactor!=0?scaleFactor:1;
         long startTickTime = startTime+rulerTickMinor-(startTime % rulerTickMinor);
-        long majorTickDist = rulerTickMajor/scaleFactor;
+        long majorTickDist = rulerTickMajor/safe_scale_factor;
         
         gc.setBackground(waveCanvas.getDisplay().getSystemColor(SWT.COLOR_WIDGET_BACKGROUND));
         gc.fillRectangle(new Rectangle(area.x, area.y, area.width, waveCanvas.rulerHeight));
@@ -75,7 +76,7 @@ public class RulerPainter implements IPainter {
         boolean drawEvery = majorTickDist>maxTextLength;
         boolean drawText=true;
         for (long tickTime = startTickTime; tickTime < endTime; tickTime+= rulerTickMinor) {
-            int x0Pos = (int) (tickTime/scaleFactor) + proj.getTranslation().x;
+            int x0Pos = (int) (tickTime/safe_scale_factor) + proj.getTranslation().x;
             if ((tickTime % rulerTickMajor) == 0) {
             	if(drawEvery ||  drawText)
             		gc.drawText(waveCanvas.timeToString(tickTime), x0Pos, area.y+textY);