I think this is worthy of double posting and bumping...
I decided to set up the JMS exporter for the terrain, and guess what I found? I found what was causing JMS to not work. I then fixed it and got this (exported JMS, converted gbxmodel to 3ds and applied texture with double sided on):

As you can see I missed half the triangles.
Normals were also wrong, plus the texture is rotated 90 degress CCW
Fixed the triangles problem, did it again, no pic (didn't bother)
Then I fixed the rotation of the entire model.
This in turn fixed the normals (don't know how that works out)
So, now that I have my JMS exporter working in a near-perfect manner, the UHMM has finally reached a usable stage! (NOTE: I don't know, actually, the model isn't sealed within itself, but then, no other models I have seen are, they just go triangle 1 = verts 0, 1, 2 and triangle 2 = verts 3, 4, 5 and so on, so this should be fine... )
Now to make it export with a skybox so that I can actually try and run a "tool structure" on it...
EDIT:
Oh, and since the terrain has 12,482 triangles, should I use 40x40 instead of 80x80 for the displacement map?
[79*79 technically, that times 2 = the number of triangles, or 12482]
EDIT AGAIN:
My pic says clockwise, it should say counter clockwise (CCW)
Look down here!
Yep, the newest version has working JMS for Terrain and Models. And, the terrain is sealed (but has no top, it's like a displaced plane), so once I add the sky box and force the edges to be maximum height, you will finally be able to make maps with the UHMM! YAAAAAAAAAAY!!
http://files.halomods.com/download.php?id=47622
Wow, now posts...
I'm working on taking my exported GBX Model (which was then converted into a .3ds and then placed into gmax) and making it work as a structure JMS (I added the skybox in GMAX and attached it, which I won't have to do in UHMM, I just need to write it out)
I now know what people are complaing about with CHIMP..
the UHMM is soo much faster...
Still exporting... God this is slow... I know I have 1 thing that everyone wants, a fast JMS export...
EDIT: (3/19)
Wow... No one has posted since the update?
Well, if anyone does look:
I do not plan on using "Ultimate Halo Map Maker" as the name for the final build. The following are possibilities:
Silent Cartographer
The Grunt (or Grunt)
Ape (guerrilla, sapien, chimp...)
[insert the name you want here]