I'm still unable to reproduce what you are seeing, but I'm curious about one thing - if you disable Settings->Touch & Pedal Settings->Enter Annotation Mode with Stylus Input, does that fix the issue? I'm curious if your tablet is reporting touch events as coming from a stylus for some strange reason. As far as the bookmarks window, something very wrong is happening with your device, as that should not be possible unless you tapped on the bookmarks icon in the song overlay, assigned a touch or pedal action and triggered that, or assigned the right icon in the quick action box to "Show bookmarks" and triggered that. There is no other action in the application that would bring up the bookmarks window. What type of device are you using? We may want to have you backup your library, uninstall MobileSheets, reinstall it, and then restore the backup to see if that helps. You can either backup the LocalState folder, reinstall the app and then copy the files back, or use Settings->Backup and Restore->Backup Library.
Mike
Mike