[HELP, IF POSSIBLE. HEAD/BODY TOGETHER WONT ACCEPT SKIN.]

Your best bet would be to join the in world support groups for the products including the appliers/skins and asking in them.

[The new Firestorm seems corrupted!]

Maybe it suddenly froze, lagged etc because you opened a group to view notices and suffered from the LL "feature" of notices not being dropped after 14 days - if you open particularly active groups it will have to load every notice sent for about a month and that will freeze the client for several seconds.