Well, I haven't had this problem, so I can't give you direct feedback, but I can suggest some things.
I take it you're using a USB keyboard? I'm using an Apple Extended ADB keyboard through an iMate...though a hub. Sometimes things stop being recognized by the computer, so what I then do is unplug and replug the hub. Try doing that to your keyboard when this happens. If that doesn't work, try reinstalling Bryce. Have you ever had this problem with other apps? Are you pre-OS X (like me) or are you using OS X? Got any funky drivers for other input devices that might be conflicting?
Standard tech-support type stuff, I know, but as someone who's had their share of odd problems (jerky mouse fixed by rebuilding the desktop file...printing problems with an ATM conflict, and I disabled extentions going alphabetically, and ~ATM was the very last - go figure :mad: ) I can say sometimes things just stop working and later start again, try unusual things and see if anything changes.
Good luck!
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