I've had my Rez for less than a week and downloaded the Swype beta the very first day. I haven't encountered this issue at all, yet (knock on wood). The only thing that bothers me is when writing comments on FB the height of the KB on portrait will cover up most of the box and I can't see what I've typed. So I usually flip to landscape and voila, problem solved
PS: The phone came (or was updated without my knowledge) with the latest update.

PS: The phone came (or was updated without my knowledge) with the latest update.