Done! Thanks for your help.
Looks great! And I like the addition of a version number :P
I'll start implementing these right away, and I'll also look into importing the text - or at least, the room numbers.
Thanks! I started working on the implementation.
Also while at it, I think I'll probably also be able to support columns and statues if you'll add them.
I'm the author of Mipui, an open-source online map editor. I'm also thinking of adding an option to import your JSON file, and was wondering if you could add additional information, in particular which squares are flooded and which rooms are round.