Yeah, if you need unusual legacy driver configurations for the software to work correctly then there's probably an issue with the software itself. Especially if it has unpredictable behavior varying by both build and system. That's a pretty big smell, especially if it's happening without any changes to code that should affect the subsystem. I observed this fucky behavior on a recently installed copy of Windows 7 64-bit with up to date installation of all manufacturer provided drivers. It wouldn't terribly surprise me if the app is having problems with the fact that my system has USB 3.1 ports, even the MS install disc has problems with that which require extraordinary measures to work around. Can't say I'm feeling very inclined to dig around in the source code to fix this problem either, what with me being called a liar for daring to mention a problem I had. I have a workaround that functions correctly on my system so I really don't give a shit, not enough to go out of my way if that's how it is.