As per title when I try to load any project (maps for GM Mode) the engine crashes before the map selection screen even opens.

I'm currently having the same issue. Everything worked fine for me yesterday, but trying to open up my project (even older backups) today has caused it to crash on the "Initializing" stage of the first loading screen.

Same here.

They're working on a fix, I expect it won't take long. Norbyte found a bug with the window title being too long, I've verified it by testing with mods of my own by shortening level names and the project title in project settings, and Larian has that mod to verify their fix on now so... Shouldn't be long

The patch fixed it.
Thanks Larian, that was quick!