Is there someone out there who can build maps with the map editor? It crashes for me as soon as I try to add tiles to the map... :(

Please help!

That's the usual behavior. The editor is very buggy and it crashes on all versions of Windows XP and newer (e.g. when the Tiles tab is selected). It's said, that it only runs (but still unstable) under native Windows ME or 98. Compatibility modes don't get you any further. You could try setting up a virtual machine with Windows Me (or Windows 98) if you still own a copy and run the editor there. It might work.

or better yet, is there a working unofficial map editor somewhere?

Hm it is very sad that the developers couldn't get this working. I mostly bought the game here on gog because of hoping the editor is working. I already have the game on disc. :(

Good question, a31!
I don't know of any.

Is there a way to make the developers repair the editor?