jordygovaerts

You'll need OpenIV for that. Open file you want to edit with it (in Edit Mode!) and then look for the texture name, for example uppr_diff_001_c_uni. Then look for the one with the latest letter (so if you have uppr_diff_001_a_uni, uppr_diff_001_b_uni and uppr_diff_001_c_uni then the last one is the one you're looking for) and rename your skin you want to import to texturename_nextletter_texturename (so in our case it would be uppr_diff_001_d_uni). Then click on "Import images" and select your renamed file. And if you want to add more files, just simply give them next letters. 
 
Hope it's not too complicated :)

i have instal xliveless asi loader end now i can conect to games for window live ? help me