This guide is only about editing, that is why I wrote "Guide to editing battlemap buildings"

I think we are very close to making new buildings, but I haven't tried it out at all. The game also makes BPI files if there aren't any, but it does not contain boundary information so units can walk through the walls. To be able to add new buildings you probably need to add some text entries, edit the descr_items.db and an entry in descr_building_battle\dbb_.txt. But that is all guessing since I do not know what the errors are when adding new buildings.