I'd like to bump this as I'm having the same problem (and the forums won't let me make a new thread. Spambot protection, I guess?)
I'm making a custom helmet and the model shows up white and the game complains that it can't find the diffuse texture, possibly because of the following
1. I have no idea how to set up addon packing properly, do my textures need to be in the data folder inside of my source folder when I link them to the mesh in O2? Does my source folder need to be in arma's directory or can it be anywhere?
3. I can't for the life of me figure out how to work with rvmats. Are they even necessary or are they just for adding more advanced stuff like normals? When typing the address of a texture in rvmats should I type the whole address (C:\...\ArmA3\myaddon etc ) or just "myaddon\data\texture.paa" ?
I've been modding for like a dozen different game engines, arma so far is giving me the most trouble :(
Edit: Well now, turns out the pbo packer wasn't set up correctly. FML. Still, I'd like some clarifications about rvmats, where can I find some proper templates to see how they work?