my favorite live wallpaper was "waterpaper" -- but, I quit using it because it was having the same problem you described.
It would work for almost a whole day, then start wigging out. I'd get a half black screen on wake up a few times, then laggy home, then it'd just stop doing the live wallpaper and go with a static image.
I never got a force close - just quit working. I thought the issue was system related and not tied to the app (since I had no fc). Well, I quit using waterpaper and switched to other live wallpapers and ... viola, no problem. so, if you're getting weird issues - just switch to a new wallpaper.
by the way, I'm rooted and flashed a rom, and overclocked, and all of that ... so, my issue may be different from yours.