Xantrokoles,
i´d love to!
There´s still quite some specular shine on these too, especially visible @ low sun / night. I also didn't quite get the details on i wanted to, because it would have involved UV editing, requiring a 3D app and at least some basic knowledge on polygonal modelling - both of which i don't have.
Concerning lightmaps - if you work with Photoshop try adding a layer with a light gray (i.e. R:190 G:190 B:190) and set it's blend mode to "Darken". This will tone down anything lighter than this to the specified level (eliminating whites).
You might also want to keep the alpha channel rather dark. I´m still experimenting with the latter.