Going into diagnostic mode.

I'm looking at your config:
1. 'Workplaces'- Some of the dummies and hitboxes are missing on the model: s_gunner_out, p_gunner, s_gunner_exit, s_commander_out, p_commander, s_commander_exit, s_loader_out, p_loader, s_loader_exit.
2. 'Addins' - Try commenting these out?
addins[ssffffff]()
{
B10A, back2, 0, 180, 0, 0, 0.1, -0.14;
DSHK3B, back2, 0, 0, 0, 0, 0.2, -0.05;
} //endof addins
3. Looking at the LOD 0 model screen, those big green cubes look a little troubling, aren't they supposed to be dummy chunks, with a consistent size (without dimensions, actually)?
there is one line I really have no idea what it does......
Im thinking it has to do with expected chunks of model. Ei DISK3 file has 4 named componets. Another possibilty is encoding of text file. But have not messed with it.
You should read the 'mkmodel' manual again

It's for vehicle selection in the GUI.
Also this line.
ostov_type[s] = tabs\ostovs_mtc80.cfgpack,spg_ostov*;
I have always thought this was for destroyed stuff that appears in next battle but what if it does something else?
From the description in 'mkmodel' it looks like some kind of vehicle-type table.