Anyone in here who read the Aleph One development mailing list some time in November may remember that I was beginning to write an (object) editor in Lua. I gave up on it because Lua simply didn't have what I needed to read the bytes from the map file, and I haven't done anything since.
Until today! I sat down and looked at my Java textbook from a year ago, then looked at relevant parts of the Java API. With a couple of hours' work, I have a Java program that reads the header of a map file, as well as the file's trailer (where level name and flag data are stored). Right now, the only thing that happens as a result is that the program prints out each map name and its game type flags, e.g.:
[XL] Infinite Rhapsody
Every Man For Himself
Kill the Man with the Ball
King of the Hill
More details are in this link: http://jonirons.blogspot.com/2007/01/jforge-juiceforge.html
and if, in the future, you want to look at all posts about this editor, check the link I included at the bottom of the post (in the Link field).