Decal Problem

Hi all - I need some help with an ongoing problem. For the past two models, I have been having problems with my decals. The first set was an after-market set for the Pegasus Mercury 9, the second set was the kit decals, made by J-Bot. In each case, th emanufacturer stated because the decals were thin, therefore fragile, I should coat them with decal film before using. My film of choice has always been Microscale's Decal Film. I applied it as per the instructions and waited twenty-four hours between applications, and another twenty-four hours before starting to use them. In every case, the decals curled up, in a couple of cases, like a soda straw. I have been able to get them to lie down using copious amounts of Micro Sol, and today, after matting the decals down, took advantage of it adhering to the model to immediately coat it with a clear matt lacquer. Now, the temperature has been hot here, but not as bad as elsewhere in the country (high 80s and low 90s), and the humidity has been through the roof. Are these my problems or should I look elsewhere? Are there any other steps that I can take to keep this from happening again? Thanks for any help you can give me.
Regards, John Braungart