Thanks, guys! The glow is ok, I guess, not what I envisioned but the best I could do anyway - no remorse!
The rock is made from Milliput standard. I found out (somewhere in internet) that it breaks nicely in layers after it has cured, leaving a really convincing slatelike edge. I press the stuff flat, 2 - 3mm thick and then press some inendentions to the surface with a real rock. After it's cured you can break it to pieces easy with fingers or pliers. It's better than real rock for bases because it's so easy to work: filing, drilling and breaking bitz off.
I tested Milliput for sculpting, but could not get the hang of it, just horrible yellow goo all over the place. It's good for filling small pores and holes tho, specially in metal or resin models, as you can dillute it with water until you can paint it on with a brush and sandpaper over it when it has cured.
Armored walkers are Slow and Purposefull.