Thanks! I think the full screen windowed option should be doable, we'll look at that for a future update. So far we haven't been able to get 8 simultaneous controllers working. If you have software (xpadder or something) that can map gamepads to keyboard inputs, that might work as a substitute.
Thank you for answering so quickly, great for the window / full screen option,
To map my controllers I use Joytokey, but I already had some problem with some games, but for now everything works for Viper League,
I hope you find the solution in the future, otherwise this solution will do the trick.
Also when I add the player 7, the game stops completely I tried on 2 different pc.