Not trying to minimize your problem but they flood for the exact reasons any of them flood.
Flooding occurs when more liquid than can be vaporized is drawn into the head or condensation from the center tube / air tube / chimney settles into the head.
Too strong of an inhale, too restrictive air flow setting, under powering, gasket not sealing, over filling, changes in temperature & altitude.
Condensation usually spits & snaps and the most likely cause if it has been sitting unused for a while, like a couple hours or over night.
It is a good idea to keep inhaling for a second or two after letting off the fire button to clear air tube & occasionally dry the center / air tube with a twisted napkin or qtip to dry condensation.
I use mainly 50/50 and it has never caused any flooding in any delivery device, including the freemax.