BetterTouchTool 4.333
I have a small external keypad from XP-Pen which has 10 keys and a rotary wheel. Using the Keyboard Shortcuts section of BTT I can configure the keys I need, including the rotary wheel.
However. Each day when I restart my Mac some of the previously working keys are no longer recognised when I use them.
The curious thing is that the affected keys still appear to be setup fine inside BTT: if I select one and look at the recorded keystroke it shows what it should. Also three of the keys still work fine each time, but two of them don't and it's always the same two.
I'm careful to File > Save Changes in BTT whenever I update anything.
The "fix" is to simply press the problem key(s) again inside BTT to re-record them and they instantly begin working again. But they'll be gone again tomorrow following a shutdown & restart! 
Thanks
my initial guess: this sounds like for some reason the reported keyboard id changes. Maybe the keyboard device reports a different one after every restart 
Could you post the json (cmd+c in BTT, cmd+v here) for a non working, and for a working shortcut?
I wonder. Later in the day I noticed that my iCloud drive - that I never use - was claiming in System Preferences to be "Full". 5GB of 5GB used. I have BTT set to sync settings with iCloud.
Sorting out my iCloud issue took a 45 minute call from Apple to resolve - their senior-level tech guy had to manually force a re-indexing of something on their side. Now I have ~5GB of my 5GB available and this issue of BTT "forgetting" my settings seems to have resolved itself.
Perhaps BTT was only able to read-in a previous version of my settings and never write-out the newer settings I'd given it?
Unrelated comment: Apple's tech support was fantastic. I don't use an iPhone, I don't have AppleCare, my MacBook was pre-owned - I'm the furthest thing imaginable from being a "customer" of theirs, yet they even called me to help. I guess they can afford it... 
