i use the scribe pen alot and notices that if i'm not using the pen pallet for a few minutes while in the PDF viewer - it won't open again until i'll quit the app and open it again. and that too is not so consistent.
Hi, I also face this problem but only when I open pdf files which are huge-like 100MB+. Have not faced this problem with smaller files. I just work around it, save my progress, restart the app and it works fine after that.. I think it must be something about the memory getting full quick or something with such large files.