Hi Dobster, Pam suggested I said something about Camembert Vs. Lactic cheeses (I am Yoav) skin slip. I don't remember that particular post but generally yes. First off, P.Candidum can grow very fast. It does need a bit of geo or yeast to make the surface pH more welcoming. There is a cheese I make where I need the skin to grow quickly. I use a strain of P.Candidum called 'Neige' and it develops within 2-3 days! Not all cultures were created equally; some grow faster and are more aggressive towards the orher bacterias on the cheese, others have more flavor or aroma.
Lactic cheese is far more delicate and to build a skin you really need geo. Using P.Candidum Without Geo you will only get the white fuzz without the yellowish skin underneath it. Being skinless means of course that you can't have slip skin.
...but if you have some sort of rind developed somehow (perhaps naturally occurring geo or cross contamination from a nearby cheese, or putting the cheese in brine)- than slip skin can happen when the temp/humidity are too high and the outside matures far faster than the inside (like french fry in a fry pan that's too hot - burns outside when the inside is still frozen). The skin grows fast, locking moisture in. Under the skin the curd breaks down and ammonianize itself, but 1/4" below it the paste is still 2 weeks away from being ready. Another reason this could happen is because the cheese has not drained properly before being salted and put in the aging container, or if it was not salted properly so the whey didn't drain. Another possibility is that the curd wasn't cut to the right size (or waited too long to cut it, which causes it to stop draining whey effectively) - so the moisture is locked in. (Heck, I once has slip skin purely because my draining mat was too dense and didn't let enough whey escape).
But the short version of it is that you need to LOSE moisture to prevent skin slip - not add more. Wrapping the cheese will only serve to lock more moisture in. If you have an 8-day-old lactic cheese in a covered Tupperware container, I doubt that you need to add any water at all to give it the 90% RH it needs. In fact, you should be wiping water beads off the box and lid and try to let it grow patiently. Even partially-open the lid. Skin will develop. I promise.
The mold on lactic or semi-lactic cheese is often more spotty and uneven than rennet. Look at aged Crottin, Saint Maure, Chaourse, etc. They are all spotty with white PC atop creamy yellow spots (from the geo). As they mature they get more sport of blue and eventually turn brown. It's all spotting.
Below are photos of 3 styles of lactic goats' cheese that I made with rinds. (I have used geo in all though) Notice the different patterns: