I ran Amber off and on for a couple of years. One of my favorite gaming stories is from Amber (the pattern ghost of Brand managed to manipulate the entire group into making him "real." Even convinced Merlin's daughter to cut off Merlin's own hands in order to steal the spikards...man, that was a fun game).
There's one super-important thing you have to have, above all else, for a successful Amber game. The players must trust the GM. Even more so than a game that uses dice, the Amber GM has to make decisions on how successful stuff is. If your players don't trust you, the quibbling and arguing will kill the campaign.