the BRB i have was already patched to the most recent. also, the RBRSR mod will not work properly if it's on the same drive as your operating system. the pedal thing i'm not sure about. i was able to assign all three pedals with no problems. try assigning your brake first and delete the assignment for brake/reverse.
i'm using a G27 if that could be a problem for you.
EDIT: RBR the game should be on a different drive. mine is on "F:\Program Files\SCi Games\Richard Burns Rally\ and it works flawlessly.