The first thing I did after reinstalling Windows was go there and download all I could could, but apparently I had missed about half of them (I assumed the drop menus saying "see all downloads" meant it was just going to show me older versions of the same driver, which in most cases it did). So just now I've gone and reinstalled all of these in the displayed order, and I do finally have the ScreenXpert app installed, but it won't boot because of an error:
So how do I get around this? Nothing has actually changed on my computer since following the instructions, MyAsus still won't show the Vivid display options, and the ScreenPad toggle button still doesn't turn the lower screen off.