In the old versions of MSN i used to customize conversations with different contacts by setting a background colour for each contact. However in the new Windows Live (the one with dp's on the left instead of right) you can't do that. You can only select one background of the contacts list that will be the same for all your conversations

Would be much apreciated if someone could make an add on that would allow me to change background colours of different chat boxes. If one already exists, then a link would be nice

thanks.

The only thing you can do is change the colour of the window. I made a script that will make it a similar colour as the contacts status. Other than that there is no way to be able to do what you are requesting sorry.