Hello guys, I'm sorry long time no answer.
Thanks for support. I was a little busy and I'm currently working on another Sansa skin. It will be really gorgeously, if you like my style.
Sansa Rockbox firmware doesn't support audio so far, so there's no any point to use skins.
Also may be theme will be ported to other players. But I think the simples way with iPod Nano =)