In http://teddyb.org/~rlpowell/hobbies/software/bw2/ you'll find what I've gotten working so for on my skirmish hack. It's a bunch of hex-edited files for the games' built-in lands, plus a land of my own.
The hex-edited files (except for Land9.chl, IIRC) will all send you to my skirmish hack...