Not a fulltimer so if ya wanna discount my thunk you are welcome to:).
Still as I understand the rudiments of mold and mildew(the early stages of mold), opening a window in wet areas or providing a lot of sun should stop growth just the same way it did for our antecedants. These types of problems were not aa big a problem in homes of old since they weren't as weather efficient.
IF mold is already in the area I'm not sure turning on an AC would be that good an idea when you think of Legionaires' disease and it's origins. I'm sure it would be fine if mold/mildew isn't present.
Were it me and I was in a high humidity locale, I'd try to keep the screen door in place, open roof vents and screened windows during the day and then turn on the AC at night. Perhaps a dehumidefier(chemical or electric) would be useful as well. JMHO.