Are you using an orbital buffer?? What RPM range can you work with on it? Keep your speed below 300 rpm with wool pads....if you can. I have not used a ton of different compounds on boats. This is what I use, and they work very well.
Once sanding is completed, start with-
I am sure there is a debate about using automotive clearcoat products to restore gel, however, the automotive products seem to work better to me. The meguirs power cut marine compound is good stuff though. I Always use that for a mid stage. After the power cut, there is virtually no need for a swirl remover, but I do it anyhow.
On another note, if you do not have one of these- (or similar) I highly recommend it. An orbital, with great speed control, makes the job very easy, harder to screw up, and less messy when applying compound. Unfortunately, it costs a pretty penny.