Hello chaps, cheers for the responses.
Yes, sealant was used around the base of the half moons.
I don't recall my mechanic torqueing the cam cover back down though.
I think he just guessed how tight he did them up.
It's a right pain as when I used to run 18psi of boost on my old T3, there was not a drop of oil in sight.
I have wound the boost back to about 24 to take a little pressure of everything but it still leaks
The picture below should show how my breather is plumbed in. Its the standard way everyone does it I imagine as we followed the bailey diagram.

Is there any other type of uprated breather system I can used to cope with the high boost or better quality half moons, cam seal and o-rings I could be using. I really want to fix the leaks but I can't be arsed if it's just going to start leaking again

Cheers,

Ollie.