So, we started working as soon as we matured the idea enough. Our progress so far:
This is our Map Editor (if it becomes something more polished to the end of the Jam, we are totally uploading it for other compos) and our current test setup for the game. We finally switched from Java to C++ (using Allegro) since we failed to find a Java framework with the features we wanted.
We have uploaded some pics of our development lair to flickr. Be sure to check them out.