New Mouse's NumPad bound mouse buttons don't work in-game.

I recently got a new trackball that had the standard Mouse 1-5 buttons, but there is a 6th button that is bound to NumPad1, similar to the Razor mice that Starcraft players use with 10 buttons on the side. It works in a large majority of game I bind it to, but not in LoL.

I've got NumLock turned on and still nothing happens. I tried reintalling the drivers, still nothing. I know the issue is attached to LoL in some way because it still works in other programs.

Anyone with experience here? Thanks.