This one is REALLY strange. I started working on a task this morning for ACRE and about 2 hours into it, after having successfully implemented the dragging listbox control the game began to crash. I reverted code all the way back to the start and the very basic steps I listed above still cause a reproducible crash for me, and for other users I gave files to test with. I have only ONCE since then been able to get it to drag with out crashing, but it then began to crash again.