Did you try something like that before launching the ROM : http://tweakguy.com/fix-wrong-pin-pattern-when-restoring-twrp-nandroid-backup/
Yes, but those files didn't exist, since I did a full wipe / reset, but here's what DID fix it... Got back into TWRP, wasn't letting me do Factory Reset / Format in Wipe menu since I had already tried wiping each partition... So... rebooted into TWRP again, but went straight to the Factory Reset so it would format Data first and foremost. Rebooted into TWRP and the password was gone... Wow that was a mess. NO clue what went wrong as I've not changed my process from one ROM to the next, but this did the trick.
What I am lost about is that it changed my "PIN" to my Google Account Password after the ROM's first boot / setup. I used OpenGAPPs Nano. Not sure if that is where it happened from or what, but man that was both scary and frustrating, lol. Whooooooooo, what a morning! I will NOT be forgetting how to fix this issue anytime soon, haha.
Edit: Have seen this before on a few other ROMs and have never experienced it myself until now. Fresh Wipe, Fresh Install, etc... Home button rarely and randomly becomes unresponsive. Hitting the power button off / on seems to refresh it without having to power completely off or anything like that. Can not seem to make it happen consistently and it's rare enough to not be a huge issue. So, few camera bugs and this... otherwise this ROM is VERY solid, going very smoothly overall.
Noticed a few things it doesn't have that PAEX does, but they're not the same ROM so yeah, duh. Request if possible: SlimRecents