diff --git a/plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/ObservableList.java b/plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/ObservableList.java
index 20237d9..d6a95fc 100644
--- a/plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/ObservableList.java
+++ b/plugins/com.minres.scviewer.database.ui.swt/src/com/minres/scviewer/database/ui/swt/internal/ObservableList.java
@@ -115,7 +115,7 @@ public class ObservableList<E> implements List<E> {
 
 	public boolean addAll(int index, Collection<? extends E> c) {
 		int oldSize = size();
-		boolean success = this.delegate.addAll(index, c);
+		boolean success = this.delegate.addAll(index<0?0:index, c);
 
 		if ((success) && (c != null)) {
 			List<E> values = new ArrayList<>();
diff --git a/plugins/com.minres.scviewer.e4.application/Application.e4xmi b/plugins/com.minres.scviewer.e4.application/Application.e4xmi
index 3245ad3..e3f7410 100644
--- a/plugins/com.minres.scviewer.e4.application/Application.e4xmi
+++ b/plugins/com.minres.scviewer.e4.application/Application.e4xmi
@@ -117,7 +117,7 @@
   <handlers xmi:id="_ru2NIEYEEeyPM8G0E2EYww" elementId="com.minres.scviewer.e4.application.handler.help" contributionURI="bundleclass://com.minres.scviewer.e4.application/com.minres.scviewer.e4.application.handlers.HelpHandler" command="_lqjIYEYEEeyPM8G0E2EYww"/>
   <handlers xmi:id="_TwU0IEYoEeyKK_icsY7Xjg" elementId="com.minres.scviewer.e4.application.handler.enabletxdetails" contributionURI="bundleclass://com.minres.scviewer.e4.application/com.minres.scviewer.e4.application.handlers.EnableTxDetails" command="_Fj1gQEYoEeyKK_icsY7Xjg"/>
   <handlers xmi:id="_htyxgHCOEeyub8CfGE1sGA" elementId="com.minres.scviewer.e4.application.handler.helpContent" contributionURI="bundleclass://com.minres.scviewer.e4.application/com.minres.scviewer.e4.application.handlers.HelpContentsHandler" command="_RdUMoHCOEeyub8CfGE1sGA"/>
-  <handlers xmi:id="__Ozu4LcxEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.handler.add_blank" contributionURI="bundleclass://com.minres.scviewer.e4.application/com.minres.scviewer.e4.application.handlers.AddBlankWaveformHandler" command="_vYAOQLcxEe294PIiYLxpfA"/>
+  <handlers xmi:id="__Ozu4LcxEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.handler.add_separator" contributionURI="bundleclass://com.minres.scviewer.e4.application/com.minres.scviewer.e4.application.handlers.AddSeparatorHandler" command="_vYAOQLcxEe294PIiYLxpfA"/>
   <bindingTables xmi:id="_95PfvnNmEeWBq8z1Dv39LA" bindingContext="_95PfuXNmEeWBq8z1Dv39LA">
     <bindings xmi:id="_95Pfv3NmEeWBq8z1Dv39LA" elementId="com.minres.scviewer.e4.application.keybinding.quit" keySequence="M1+Q" command="_95PfvHNmEeWBq8z1Dv39LA">
       <tags>type:user</tags>
@@ -202,11 +202,11 @@
         <parameters xmi:id="_4ZeEQXabEeWwZ-9vrAR2UQ" elementId="com.minres.scviewer.e4.application.parameter.5" name="com.minres.scviewer.e4.application.command.navigateTransCommand.parameter.dir" value="prev"/>
       </children>
       <children xsi:type="menu:MenuSeparator" xmi:id="_cxgs4Lc0Ee294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.menuseparator.1"/>
-      <children xsi:type="menu:HandledMenuItem" xmi:id="_NFfK0LcyEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.handledmenuitem.add_blank" label="Add blank above" command="_vYAOQLcxEe294PIiYLxpfA">
-        <parameters xmi:id="_or7iYLcyEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.parameter.15" name="com.minres.scviewer.e4.application.commandparameter.add_blank" value="before"/>
+      <children xsi:type="menu:HandledMenuItem" xmi:id="_NFfK0LcyEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.handledmenuitem.add_separator" label="Add separator above" command="_vYAOQLcxEe294PIiYLxpfA">
+        <parameters xmi:id="_or7iYLcyEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.parameter.15" name="com.minres.scviewer.e4.application.commandparameter.add_separator" value="before"/>
       </children>
-      <children xsi:type="menu:HandledMenuItem" xmi:id="_ecbWkLc0Ee294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.handledmenuitem.add_blank" visible="false" label="Add blank below" enabled="false" command="_vYAOQLcxEe294PIiYLxpfA">
-        <parameters xmi:id="_ecbWkbc0Ee294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.parameter.15" name="com.minres.scviewer.e4.application.commandparameter.add_blank" value="after"/>
+      <children xsi:type="menu:HandledMenuItem" xmi:id="_ecbWkLc0Ee294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.handledmenuitem.add_separator" visible="false" label="Add blank below" enabled="false" command="_vYAOQLcxEe294PIiYLxpfA">
+        <parameters xmi:id="_ecbWkbc0Ee294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.parameter.15" name="com.minres.scviewer.e4.application.commandparameter.add_separator" value="after"/>
       </children>
       <children xsi:type="menu:MenuSeparator" xmi:id="__Ubd4M1eEei6rfTGo88R-w" elementId="com.minres.scviewer.e4.application.menuseparator.0"/>
       <children xsi:type="menu:Menu" xmi:id="_mAA6sM1bEei6rfTGo88R-w" elementId="com.minres.scviewer.e4.application.menu.view" label="View">
@@ -286,8 +286,8 @@
     <parameters xmi:id="_6KsZcHr9EeWVM_sKoXvptg" elementId="com.minres.scviewer.e4.application.command.addwaveform.where" name="where" optional="false"/>
     <parameters xmi:id="_7T1TcHwIEeWv0Y5uF2QN5w" elementId="com.minres.scviewer.e4.application.command.addwaveform.all" name="all" typeId="" optional="false"/>
   </commands>
-  <commands xmi:id="_vYAOQLcxEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.command.add_blank" commandName="Add Blank Waveform">
-    <parameters xmi:id="_g_HnsLcyEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.commandparameter.add_blank" name="where"/>
+  <commands xmi:id="_vYAOQLcxEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.command.add_separator" commandName="Add Separator">
+    <parameters xmi:id="_g_HnsLcyEe294PIiYLxpfA" elementId="com.minres.scviewer.e4.application.commandparameter.add_separator" name="where"/>
   </commands>
   <commands xmi:id="_AxH6sIl_EeWxJ_wPkM6yGQ" elementId="org.eclipse.ui.window.preferences" commandName="Preferences"/>
   <commands xmi:id="_KlGlsIoNEeWxJ_wPkM6yGQ" elementId="com.minres.scviewer.e4.application.command.set_them" commandName="Set Theme Command">
diff --git a/plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/handlers/AddBlankWaveformHandler.java b/plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/handlers/AddSeparatorHandler.java
similarity index 95%
rename from plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/handlers/AddBlankWaveformHandler.java
rename to plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/handlers/AddSeparatorHandler.java
index 3055d93..50720e1 100644
--- a/plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/handlers/AddBlankWaveformHandler.java
+++ b/plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/handlers/AddSeparatorHandler.java
@@ -24,9 +24,9 @@ import com.minres.scviewer.database.IWaveform;
 import com.minres.scviewer.database.ui.TrackEntry;
 import com.minres.scviewer.e4.application.parts.WaveformViewer;
 
-public class AddBlankWaveformHandler {
+public class AddSeparatorHandler {
 
-	public static final String PARAM_WHERE_ID="com.minres.scviewer.e4.application.commandparameter.add_blank"; //$NON-NLS-1$
+	public static final String PARAM_WHERE_ID="com.minres.scviewer.e4.application.commandparameter.add_separator"; //$NON-NLS-1$
 	
 	@CanExecute
 	public Boolean canExecute(EPartService partService){
diff --git a/plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/messages.properties b/plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/messages.properties
index 37aed50..8c31e4f 100644
--- a/plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/messages.properties
+++ b/plugins/com.minres.scviewer.e4.application/src/com/minres/scviewer/e4/application/messages.properties
@@ -83,7 +83,7 @@ marker=Marker
 marker_text=Marker TExt
 rel_arrow=Relation arrow
 rel_arrow_highlite=highlighted Relation arrorw
-blank=blank waveform entry
+blank=separator
 UpdateHandler_URI=http://https://minres.github.io/SCViewer/repository
 UpdateHandler_10=Information
 UpdateHandler_11=Error