You'll note from the previous post that I've basically dremelled out the opening to be the same size as the circular gate on the analogue stick. It's not ideal, as there's basically nothing stopping dust and crap from getting into the innards of the stick; but, I can't really do much else at this point without coming up with a totally different mounting method. That's not impossible, but for now I may just accept that I'll likely have to change the stick every so often if it gets gummed up inside.
Here's what it looks like with a thumbstick on:

Most of the dust protection dome will have to be removed for it to actually rotate, so that won't help keep the guts clean. I did wonder about those weird "aim assist" rubber boots you can get but we'll see. Anyway, ergonomically it feels great so once it's all up and running I expect great things

The throttle wheel potentiometer does clash with the stick body, so that's had to come out; one of the wires was detached anyway, so I just snipped it off. I wasn't convinced that a throttle wheel would be much use on this device anyway, but I must admit once I got it in my hands, the position of it feels OK. I had considered putting some momentary switches in the hole vacated by the wheel, but I think that would look a bit shonky and they'd be hard to press in that location anyway. I ordered a 6mm shaft ALPS rotary encoder to replace the bulky pot, that will fit in place without clashing, and should be able to be wired up to the teensy as a scroll wheel; how PC games will deal with two scroll wheels I don't know, but anyway that's a nice to have for the future when I get the programming for it sorted out.
How much rewiring I do internally will be determined by whether I keep the N50 PCB in place or not. The main advantage of keeping it in play would be that it would minimise the amount of wiring I have to do (I am
not skilled at soldering!), and I would be able to use the Belkin software for mapping the keys, including setting up shift states. The main advantage of ditching it would be that I can just have the Teensy LC doing everything and just one USB cable coming out of the thing, also the PC would just see one controller so it should minimise compatibility issues. So, I thought I'd assemble the device and see if the original PCB worked.
Connecting it to the PC seemed to go OK - the LEDs lit up briefly, it was recognized as a controller, and drivers seemed to get installed OK. Fired up notepad to see if the keys functioned as keys - nothing. So, I tried joy.cpl, which showed it as a 3 axis 10 button controller; but, in the test panel, nothing functioned. Bear in mind that right now the only thing connected to the PCB is the keypad, as the throttle and Dpad are cut away! So, now I have no idea whether the PCB is fritzed, or whether it's just the keypad membrane that is dodgy.
I wasn't planning on keeping the dead flesh rubber dome keypad anyway, so next on the agenda is fitting Cherry MX keyswitches (blues - I know, I know, but this is being done on a tight budget and they were cheap!!) and wiring them up in a matrix. I'm thinking that I should just copy the matrix from the existing membrane, so I can wire into the N50 PCB to test it again, without needing to add resistors and diodes (they're already built into the PCB). However, I'm struggling to trace all the lines on the membrane

I might need a bit of help here!! I'll post some decent quality images of the membrane tonight, if anyone could help me trace it out and come up with the matrix wiring for the keyswitches, that'd be great.
If it turns out the PCB still doesn't work with the Cherries wired in, I'll have to bite the bullet and go full Teensy control - which is where I'll also need to figure out resistors and diodes. Again, any help gratefully appreciated
