The clutch in my cav turbo is new but the car was sat for nearly 6 months only a matter of weeks after the clutch was fitted. There is obviously gonna be a bit of crap on the clutch, I had similar problems with an SRI, but how long do you reckon it will take before its cleared?
You could try reving the engine to about 2,000rpm and just feeling for the biting point on the clutch and holding it. That would clean any crap off but its the area enclosed? Surely no crap or dirt could get in?