For the heck of it (though I know it likes to crash constantly and randomly when picking up items), I enabled this rule again and played a quest some. I got to a room where there were some keese and moblins. I flung the boomerang at them as they spawned at one point in the room and a moblin threw a spear right when the boomerang was about to hit it. Apparently, ZC proceeds to crash with the boomerang sound still playing and an illegal operation box of some other program pops up. After I closed that, my sound was completely gone (system sounds, Winamp, ect). I tried to open Zquest so I could go disable the rule before restarting to get sound back, but Zquest illegal operationed on me.
This was the windows version.
After restarting, Zquest is back to normal and everything, but that was just freaky.