Yes to uninstall CSSU or revert it to a version that didn't touch pdf reader, however it is not needed. You can just simply switch off scrolling and use the old method to change pages, that is working as before. or if you prefer scrolling just before you get to the last page switch off scrolling. Scrolling can be enabled/diabled via a button on the bottom of the screen ( white sheet with big red x in the middle, kinda like error 404 in a browser). Not in full screen mode that is.

Hope that helps.