Are you sure?

Just a quick suggestion: Why on earth haven't you included a question that confirms that you want to delete and edit stuff from a wad? Because if you don't have such a feature you'll most likely screw up your wad file sometime. It is good that you have an undo feature, but this is another step before the undo kicks in and catches the mistake.

That's why XWE keeps back-ups.

But I would like to see a confirmation.

I suppose the Undo feature doesn't record it either

That's mostly for noobs; otherwise speed is much more important than a possible mistake now and then (and I don't remember ever deleting anything I would not have clicked "Yes, I'm sure" on, anyway).

If he were to add it (in sake of people unfamiliar with the program, that are afraid of messing up), hopefully it'd be disabled by default, so that expert users don't have to alter more settings when installing the program.

Im not in favor of this either. If it must be added then I certainly hope there'd be a way to turn it off.

Adding such a feature would ofcourse have to have an option to disable this feature if you so want.

This could be added, but I don't see the point. What does an extra "Are you sure?" question prevent? The odd case when the user clicks or presses Delete, but then goes "Oops, I didn't want to do that". You answer No, and nothing happens. However, you can just as easily click Undo in that case.