First time i did it i also had strange colors, but in my case, i was able to config each monitor.
This weekend i bought a Samsung led fhd sf350fhu 24". I am happy with it.
So now i have my main laptop screen at full hd my new Sansung 24" at Full HD via HDMI and an LCD TV Sansung via RGB at (1366x768)

The LCD TV with HDMI can make fullhd but with VGA can only output 1366x768. Is this normal?

Anyway i have a question now:
My Laptop has a Nvidea GeForce 745M and a intel onboard card.
So when i use HDMI and VGA is he using the Nvidea or the onboard card? I Guess if if is bu duplication is the Nvidia, but what about expantion screens? Is is all the Nvidea or does he uses the onboard card?