I still would like a way to get custom content into the game, but i'm one of those windowy people.
I can understand why Illwinter wouldn't want to release the app. We would have to figure out:
-Navigating the interface,
-The commands needed to build the castle mesh,
-The proper size of the models,
-The commands needed to work out UV unwrapping,
-How to apply the textures,
-Whatever flag/command is needed to determine where arrows and stuff come out of,
-The way to place the model into the battle scene properly,
-The text commands needed, whatever they are,
-The .d3m format details
-other stuff i can't think of right now
Quite a bit to work out, but I'd definitely respect anyone who can do that on their own.