[Can't Assign Power Use To A Controller Button]

Yeah well i also having problems with this and because of this the keys for the powers dont work, granted i can assign the D-pad to previous power and next power, but i cant assign a key to Activate power, so its no good, i have to use my computer mouse button to activate it.  Whats up with this, PLEASE FIX THIS!  this is nuts

Thank you

PS.  I cant even play this!  Game is useless to me.