YOU MUST, I STRESS MUST do a factory reset after this process. Otherwise you will get eratic behaviour and force closes.
If you still get force closes you missed a line in the instructions. Please follow this:
http://androidforums.com/samsung-behold-2/35487-galaxy-stock-android-behold-2-flies-3.html#post263426
Force close = u didnt factory reset or u missed that line.