The symptoms of my reader are indeed identical to those of the issue you mention Mark, except they happened with Zork. A reset of the tap and swipe options did nothing (I did that several times already), so I just went with uninstall. I then installed PRS+ 2.1 alpha, and everything is fine again.
Edit: thank you Analogus, I feel less alone
I hope you'll be able to figure it out without too much trouble.