Which Configs?
I've moved everything, including .objects file from the folders and it starts up fine. Moving objects one by one back into the folder to see if any particular one is causing the issue. If I have them all in there at once, the game won't even start!
UPDATE - OK, I got into the map, however, most of the objects are missing their textures, even though it's clear that they are all where they need to be, and the configs all have the correct titles, lines, etc. It's as though the game has to recognize that they're there. I have to go in manually and help it find its own config again.