Okay: Performed mod surgery and Factorio (with all mods I'm using on this run) appears to run and load normally, with one exception. So it looks as though, somehow, maybe the Quenching Tower PNG got corrupted or deleted. No idea as yet how that could have happened, but <shrug>.

After reload ...

I've taken the game all the way back to Vanilla + pYCoal, but pYcoal is claiming a dependency on Factorio Standard Library (stdlib). If I include stdlib, I get the error.

I was using all pY mods as well as a handful of others and ran perfectly for weeks, keeping things updated.

I've checked for ...

Ran a search here to see if anyone else has this, but it may be just me, somehow...

__pycoalprocessing__/graphics/entity/quenching-tower/quenching-tower-anim-mk02.png failed (-105)