diff --git a/GUIs/GuiLogger.mlapp b/GUIs/GuiLogger.mlapp
index 36f63ca..d4e0f75 100644
Binary files a/GUIs/GuiLogger.mlapp and b/GUIs/GuiLogger.mlapp differ
diff --git a/Local/runDiodeLaserScan.m b/Local/runDiodeLaserScan.m
index ffe55ad..f2b384d 100644
--- a/Local/runDiodeLaserScan.m
+++ b/Local/runDiodeLaserScan.m
@@ -1,17 +1,17 @@
 %show_in_daq=true
 function runDiodeLaserScan()
-    if ~isValidBaseVar('Collector')
-        runCollector();    
-    end
-    Collector = evalin('base','Collector');
+    % Get the unique instance of MyCollector
+    C = MyCollector.instance();
     
     name='DiodeLaserScan';
-    if ~ismember(name, Collector.running_instruments)
+    if ~ismember(name, C.running_instruments)
+        % Create an instrument instance
         Instr=DiodeLaserScan('Scope','DPO4034_2','Laser','ECDL850He3',...
             'name','DiodeLaserScan');
-        addInstrument(Collector, Instr, 'name', name);
+        % Add instrument to Collector
+        addInstrument(C, Instr);
     else
         warning('DiodeLaserScan is already running')
     end
 end
 
diff --git a/Utility functions/App utilities/deleteInstrGui.m b/Utility functions/App utilities/deleteInstrGui.m
index 934ecaa..9f270fc 100644
--- a/Utility functions/App utilities/deleteInstrGui.m	
+++ b/Utility functions/App utilities/deleteInstrGui.m	
@@ -1,23 +1,38 @@
 % Delete Instrument object, clearing the global variable corresponding to 
 % gui name and then delete gui itself   
 function deleteInstrGui(app)
     %Deletes listeners
     try
         lnames=fieldnames(app.Listeners);
         for i=1:length(lnames)
-            delete(app.Listeners.(lnames{i}));
+            try
+                delete(app.Listeners.(lnames{i}));
+            catch
+                fprintf(['Could not delete the listener to ''%s'' ' ...
+                    'event.\n'], lnames{i})
+            end
         end
     catch
-        warning('Unable to delete listeners')
     end
+    
     try
-        delete(app.Instr);
+        % Check if the instrument object has appropriate method. This
+        % is a safety measure to never delete a file by accident if 
+        % app.Instr happens to be a valid file name.
+        if ismethod(app.Instr, 'delete')
+            delete(app.Instr);
+        else
+            fprintf(['app.Instr of class ''%s'' does not have ' ...
+                '''delete'' method.\n'], class(app.Instr))
+        end
     catch
+        fprintf('Could not delete the instrument object.\n')
     end
+    
     try
         evalin('base', sprintf('clear(''%s'')', app.name));
     catch
     end
     delete(app)
 end