how this work
 

on www.bsplayer.org/html/skins i upload my skin, and there is no picture and you can´t download it, i don´t understand how this works

it writes "skin" and "browse" and i upload *.bsz, and dont work

Just be patient, and somebody will create the previews for your skins. Wouldn't hurt with a small explanation on the upload page though.