I paraphrase here a post by UberSkippy on my PopUps plugin;
If you put something that has a limited use like a stack of morale pots into a slot and use the last item it throws an error.
That alone is not so much of an issue, but when it happens I also seem to loose access to what ever is in my 1 slot of the main bar. The Icon for whatever skill is still there, but if I push the 1 Key nothing happens.
I cannot seem to find why this problem occurs and as it is not peculiar to my plugin (UberSkippy has had the same problem with PopUps,BevyOBars, TonicBars and BuffBars) I turn to the community - is this an issue with Turbines code?