Hi there, thanks for this guide- it was useful though didn't quite get me all the way there. I, too was hung up on the missing .bmp files, and did the file removal before getting to that point, so I had to backtrack a good ways.
But the main issue I'm having, is that I get the controllermap app working, and the app hangs or becomes unresponsive/sluggish when identifying the analog sticks. Then it never goes further than identifying the vertical axis on the right analog stick. I have tried this three times and am using a bluetooth 8bitdo NES30 Pro gamepad. I followed this guide to get the bluetooth working. https://bbs.nextthing.co/t/bluetooth-pairing-pastebin-session/6727 I also suspect that this controller has a tilt sensor and that the other axis registrations may have accidentally been the tilt. There is no documentation of this, but the controls' similar layout to ps3 and the optional firmware I mention below make me think it might.
I am going to try updating the firmware on this controller tonight and see if that solves anything. Also, the instructions/manual on this controller are in pretty bad Engrish and don't even mention several crucial functions and/or buttons. I also noticed that this controller has an optional PS3 mode firmware you can add to it, and I have a PS3, but got this because I wanted something more compact. I noticed a guide however for getting a ps3 controller to work, though it is said to be difficult. I may try that if I get desperate.