@leitmotiv
If I understood it more I would tell you.
If it were just a discrepancy of a name for the driver of xbox controllers, but it seems to have other uses and I don't know if it even is a xbox controller driver.
When enabled it creates an assigned number of virtual controllers, gamepads can be mapped through these and there is a technical guide to advanced controller mapping on the website here regarding these two things.
It is not part of the core install, I think the xpad driver works for xbox controllers.
Though I still don't know for sure if this is only of significance to player two or if at all. The way I think it applies to some of the controller problems is that player two will instead be a virtual controller and the controller that you'd like to be player two will instead be player 5 or something. But these things... there are a few layers and I know maybe 1/5 of them, you'll have to try uninstalling it at least and with luck control assignments will be naturally working for you.
