Im not a mod (well not on Elitefitness anyway) but see my other post on the xenical issue. Hope you dont mind me jumping in!
Diet - You have to have a lowish to low fat diet or youll have probs. Pro and carbs should be as normal but still regular. fat must be low and regular. The UK guidlines (seen at www.nice.org.uk - click throu to the guidlines for orlistat)) are less than 30% total energy fat - though this is still a little high in my opinion.