It's written in Python and requires pygame to run; it'll spend like five seconds creating a map for you (or 30 if you configure for "huge" maps), and then save the image to the current directory and quit. I've commented a bit in it, and you can find some explained configurable options up at the top. If you run into issues or have any questions/comments just let me know! I'm happy to help. :)
The main downside is you have to add in the doors and room numbers yourself, but I couldn't see a way around the former. Doors have a big impact on the implied usage of the space, and I don't think a random generator would do even a passably good job at placing them for a map like this. The room numbers... I left 'em off because I want to use my room generator to make a list of rooms and then assign those numbers to the floorplan according to my whims.