... the supplied IR remote 'OK' key is flakey (it's like its not polled 100% of the time - needs multiple clicks, there's no issue with it normally).
The remote control configuration of my build only differs from the last official one in terms of the functions of a couple of buttons, but the timings are the same. I still think that there will be something wrong with the OK button or with the batteries. I still think that there is something wrong with the 'OK' button or the batteries are partially dead. (But the first one is more suspicious.)
Bluetooth is on, shows my bluetooth remote, but it can't connect
...
I use a a custom .hwdb for my bluetooth remote, installed the Aeon MQ skin, but otherwise no other changes.
Unfortunately, in the case of the Bluetooth connection, I cannot provide more specific help, because it is not really my area of expertise. However, since I managed to pair and connect 3 devices at the same time based on the screenshot above (a keyboard, a mouse and an audio device), I think the issue is not on the side of the box.