Hi Edward,
I think that your physics teacher was right but something makes it much harder to get to a low RH at a low temperature. I don;t really understand it but I think it has to do with RELATIVE humidity versus absolute humidity.
I'm away from my business at the moment and don't have the cocoa butter content to hand right now so will get back when I return. The polishig agent is from CAPOL (5021 as I recall) and there is also the shellac layer to consider too.
Colin