As far as hardware goes, since this board seems to have had a lot of solder issues, let's just go through and validate every single one of the IO ports.
IN0...IN7 are nonfunctional due to the DAC being flatlined; all testing on them will have to be tabled until I rework the DAC that I somehow forgot to do earlier. I swear I had got to it... this is what happens when you're doing bringup in between parenting a toddler I guess lol. I should keep better notes.
All of the unbuffered outputs (OUT0-3) work.
All of the buffered unidirectional outputs (OUT4-7) work.
All of the bidir IOs (IO8-11) work as both inputs and outputs.
I strongly suspect the inputs on 0...7 will work fine once I fix the DAC. Guessing just bad soldering since the SPI bus to it looks fine. Just mad I didn't do that already as I thought I had finished the rework...