Another person on the team tried to insert this simple building also, with one hidden resource requirement ("river" - as it is a river port building). Sure enough, the building was able to be built in every single province in mine, but his just automatically CTDs. I guess I just have to recopy all my files and start from a fresh 1.5 build. But I was almost at that to start with - and I think these are the only changes I've made - but I do feel like the problem has to do with my not understanding the way the map generation now works. It seemed so easy in 1.2, but now with the different subdirectories I don't know how to handle it. I've not seen a map.rwm in the imperial_campaign directory yet - and I didn't quite understand monkwarrior's method of creating a rwm file using the prologue (was that right?) and then copying it over(?). Sorry to be a pest about this issue, but there is definitely something that has changed here from 1.2 to 1.5 and I just have to figure out how it applies to the mod files we have. It's too bad changes that were introduced here were not explained really. But you guys are giving me hope that there is a way around it (I just don't see what it is yet) .