if the door hinge screws refuse to move, this trick may work.
make a little bowl out of RTV silicone on the screws after scraping some of the paint, this creates a little hydraulic pressure required for the liquid to penetrate.
Mix half n half ATF and acetone, put it in there for a while, do not inhale the fumes, this concoction will move rusted marine parts and will surely move those little screws.
If all else fails - welding torch and a candle work nice - heat and apply the wax - the wax will be sucked into the threads.
