I noticed that if I interrrupt (control-c) out of a cnee replay, I sometimes end up with a keyboard that is in a state where typematic (repeating a key when holding it down) does not work.
It can be fixed manually with the command
xset r on
but it took me a long time to figure this out. Would be better if SIGNINT (etc) are caught and cnee itself would make sure to restore the setting before exiting. Quite possibly the bug applies also to xnee, gnee, pnee (etc) variants.