sorry to bother you again
but I must tell you that I can't paint any skins for the stands worth sharing
some comments on getting the stand in the game I can give - perhaps they are useful to you and may explain my first statement - as always the few things that are not working as expected or due to "user error" are mentioned not all the "good things" (I admire the stands btw)
I started with gezerre's z3d file (the transparent section.gp4 you posted is missing the chairs) and your templates
!! the templates must be a wet dream for those who work regularly with Photoshop !!
even I with very limited experience and using GIMP could get some working tgas together after a short time:
for the transparent part I used a black/white alpha channel and DXT5 semi-transparent file format (so the glass isn't there, for the other things it doesn't matter I think)
that's how it looks ingame
comment on shape: some parts are not aligned (roof on the right side for example - see green mark in picture)
comment on textures: the plane behind the top monitors could use more shadow imho
so - why won't I paint more
the templates are beyond the scope of my skills and also with its size and number of layers beyond the power of my 6 year old pc
sorry again
xandy