The problem right now with zmodeler 1.07b is that there isn't a good way to export/import to a universal format which preserves vertex normals. .obj import does not basically exist in zmodeler 1.07b, and that format allows for universal exchange like fbx or dae. So, I was thinking of developing a python export tool, but if anyone is out there, let me know. Also, source code to z3d format does exist, and it can be downloaded in zanoza website. It just comes down to writing the code at this point. Import would be nice too.
Things that are clear:
1) Blender should always triangulate before export as zmodeler 1.07b is triangle-only.
2) Group should be treated as united object.
3) nx,ny,nz all refers to vertex normals
4) uv is apparently 3d, but z can be 1.
5) Material seem pretty basic, not sure what to do from here.
EDIT: Could someone edit title? 'for zmodeler 1' should be 'for blender'