Ah, also, the free winapp will NOT run on Windows 8 RT (or windows for any architecture besides Intel), so the Windows 10 for the Pi2 will NOT run winapp.
Sorry about that.
Instead, you might want to look at a
Winbook tablet: There are some out there that dropped to $60-$70 (they can be found for as low as $50), running full Windows 8.1 on a quad-core intel cpu with a standard USB port--that would run the winapp just fine. They're apparently dumping them for some reason, possibly due to the small (and low resolution) screen size and limited battery life.