Maybe just trashing the threads is enough in these situations, but contact mprep about it as he's the mod of the alt board and often the one who issues bans for giveaways.
My main account
khaled0111 has been temp banned too for the same reason.
What I can't understand is that the giveawy thread was in the Games and Rounds sub-section and I don't see how replying there could be against forum rules.
Maybe it can be appealed on these grounds if so.