Condensation occurs when there is a sudden sharp change in temperature. Therefore, in order to minimize condensation on your refrigerated cakes, ensure that you have a cool air conditioned room to transfer the cake to when it leaves the fridge. An air conditioned room has the added benefit of having drier air than normal (if you live in a place with 90%+ humidity 365 days a year as I do). If you are able to gradually raise the surrounding temperature, you can minimize condensation and in most cases, I can almost eliminate it completely.
Chef Nicky - The White Ombre (Singapore) - http://thewhiteombre.com - http://www.facebook.com/thewhiteombre