I'm considering opening a thread for a project to fix all of the problematic vanilla definitions so that they adhere to the restrictions imposed by patch7, but still yield full diversity as far as alternate model parts and color variations. I think it would be useful for everyone doing unit packs, color or variety modding to have a reliable base pack to work from. I do think I'll wait to see the next beta patch before I commit to any substantial work though. If they don't address the problem, or only implement a partial solution like I have done in the two examples I uploaded, then I think I'll carry through and do a full overhaul... examining and rearranging the affected unit and parts definitions from the bottom up.
For your project, do you look at the diffuse texture alongside the color mask when working on color schemes? I would definitely recommend it (especially now) as you can easily see at a glance which parts of a model
should be treated and by which color (red=primary=mask0, green=secondary=mask1, blue=tertiary=mask2). Then the mask switches in the definition will override the default color placement for individual variants. If you don't see what you expect, the problem almost certainly lies in the definition files not being suited to the new restrictions (whether that's intentional, an oversight or a bug remains to be seen). In all cases I've experimented with thus far, it's fixable. And the game is definitely still rendering colors on all 3 rgb channels, so no worries there.
Sometimes the color masks use fewer channels than you might think...
Persian tunic#2 (2 colors)
Eastern basic tunic#2 (3 colors) Notice some of the detail comes strictly from the color mask itself
Iberian tunic#4 (3 colors and what looks like a blend. Also, there are gradients present in the red channel)
The last example are really nice tunics that will never appear under current circumstances, so I thought I'd use Iberian as a test case for a complete fix. Splitting up the tunic definition was simple enough, but finding all references to that definition (i.e. every unit that wears it or the other variants) takes a bit more time. Best approach is probably to index the variantmesh folder for fast searching. In any case, the solution works perfectly.
Here are Iberian Mercenary Swordsmen, before and after... a really good example of how gimped the variant system has become
EDIT: Hey look, you released
. Checking it out now.