I also have noticed a couple of errors in the latest Screenpad software, but not like you have described. The developers have done a great job updating the software regularly, but as more features are added/adjusted, naturally they're not all working smoothly at every release.
Have you tried reinstalling the software? In my version the "maximise over both displays" option is available next to the box for screen #2. It seems you might have some kind of configuration problem, I would recommend making sure everything is up to date in Windows Update, Microsoft Store and the MyASUS App. Also check that your BIOS is up to date, though I do not know how far they have continued to update the UX481 models since the release of the UX482 and above.
As for the touch pad option try tapping then holding for a short moment before trying to frag the icon into the menu list. I noticed that this is a bit sensitive for this version and hopefully they will get to fixing that in the next version.
email4doeI don't doubt there are issues but you will have to be specific if you want them fixed. Asus have been quite good about implementing feedback from these forums into updates so I would encourage you to start a new thread for each bug you are experiencing. It usually comes back as a great feature when someone points out room for improvement so your effort in sharing would help all of us!
Too many issues with the ScreenXpert 3 on my new duo to mention. When is the bug free version coming out?