The Onza is a 0815 Pad working with the 360 driver for Windows. Usually it works just as any normal 360 pad would. Why won't you provide a default mapping for this controller then?
Unfortunately we can't provide mappings for gamepads we don't own! I've never actually heard of the gamepad that you're talking about, not that that means much -- I know pretty much the "big two" and that's about it.
The cool thing is, you can set up mappings for any gamepad at all using the control settings, so you never have to worry about your gamepad not being properly supported. If you get a good mapping for a new kind of controller and you'd like to share that others, please feel free to share your inputbindings.dat here on the forums. If you tell us the controller model (which you already did), we might be able to actually include that with the game itself so that future players don't run into the same issue.
Thanks for your support!