The bike was delivered back to me this morning with the problem sorted out and a fairly minor apology. You guys were right in your diagnosis of the fault, the rubber seal, with the main culprit being the dopey mechanic. I'll take her out for a good spin tonight and all this will be forgotton. Cheers again, ...Deasun...
seated properly - as soon as you "prime" the system (when you turn the key and hear the wirring noise) if its going to leak anymore - it will leak then as the system builds pressure in the fuel lines.
Surprised that they didnt start the bike and check it runs ok anyway after the belt change.