Chat windows customization
 

I wonder if there is some way to customize the chat and combatlogg window so that the combatlog is sharing space with another chatwindow containing only guild, whisper and classchannel. So that I in example If can keep track of both the important windows and the trade at the same time. So the guildchat wont be flodded with other ****.

If you check the "Info Panel Plugins" section in nUI's download area, you'll find a plugin there that allows you to have a separate window for Guild Chat in the info panel.

http://www.wowinterface.com/downloads/cat125.html

That should accomplish what you're looking for.