Best guess,
there is some form of solvent swelling going on. typically you will see this sort of pattern when solvent is introduced to cured paint. As in wiping it with some form of solvent, which then swells the cured finish and it cannot absorb the solvent so it puckers.
Normally this would be say, enamel, with laquer put on it,

I also agree with Mark. Remember, there is no chemical bond between Rustoleum (enamel) and dope. just the mechanical bond. so if any solvent or oil or whatever causes the enamel over the top to swell, there is no chemical bond underneath to hold it together.

Something similar happen to a classic plane I had that what upside down in a work rack. The fuel line burst and all kinds of fuel pored into the engine compartment (and through the vents to run down the topblock). I didn't realize it had gone to the top of the plane and it sat like that for about 10 minutes. When I flipped it over, it looked just like this all the way down the nose. The plane was dope from the wood up with catalysed polyurethane topcoat. Same problem. There is not much chemical bond between dope and urethane so there wasn't enough adhesion to hold things together. Took a lot of cleaning and sanding, but it was eventually fixed (shame the plane very flew worth spit - it was a pretty thing).

Actually, those are alien runes.  They are trying to communicate with you the only way they know how!  Beware of being in open spaces without your head covered in aluminum foil!!!