Paper Link in Progress not going so well

I'm making a Paper Link game but it constantly freezes after you let go of the left or right key. If anyone can figure out the problem I'd be very greatful. I stressed over it for 2 hours and I can't figure it out.

First problem was you were doing a method call in the "during" phase of the "event while" - thus giving a new call each time the while was evaluated and eventually having a very long string of pending calls.

Tried to fix it with a while loop in the method itself, but had a new problem - couldn't get the "end" condition to register and terminate the while properly.

Eventually, after several crashes, I went to the attached, which is pretty much the same thing done the hard way. Hate infinite loops - but also get tired of crashing every few minutes.

Once again "event whiles" look like something to avoid in Alice 2.0 - didn't see an obvious way to do that in this case, however.

THanks for the help!