My neighbor's laptop.. A shop, down, in my building; he was installing 8.1 on a brand-new computer, for his wife and the touch-pad would NOT work correctly - unless the driver was loaded DURING (before) teh Windblow$ installation; nuts, right?! (Mouse would work w/the left and right buttons reversed)
The one thing that I can think of, is... Did you use a retail, OEM, DVD to set up; or, some download (you know what I mean); & in any case, NOTHING should be surprising when it comes down to Windows 8.1...
In any case, hope you can work it out! =)
P.S. Replying, just, so that I can stay on top of this; curious!