Added after 1 hour 37 minutes
It was fixed by re-installing the game.
New here? I'm Roha — want a quick tour?
My map generator isn't working. If I just click "generate" and create a map, it works fine, but if I try to edit something myself (castle, hero, number of players, etc.), it gives an error saying it can't create the map. What's the problem?
It is quite possible that this is related to the pre-installed template – it may not support certain parameter changes (for example, some templates may only have a specific map size, etc.).

I don't need an editor, I need a map generator!
Nothing works for me.