I’m using Xojo 2015 r2.2. I want to copy the event handlers for a control set containing a pushbutton. The moment I right click on “event handlers” and select “copy” Xojo crashes. I created a brand new app to test this. I dragged a new pushbutton onto the default window. I made it a member of a new control group. I added a “Mouse down” event to the set. Again, as soon as I select “copy” from event handlers I get “This application has encountered a fatal problem and must be shut down.”
I can confirm that. You should file a Feedback report.
Workaround: select all events handlers of the control set instead of their parent node “PushButton1 Set” > “Event Handlers”.