here is a picture of the cracking

That is called alligatoring, believe it or not. Rustoleum is over rated.
Good luck. I wish I could offer you some help. Try Googleing "alligatoring".

bad and or improper prep and or application, not the paints fault( most likely)

I'm with Christophern - it's probably something that was left on the surface after washing. Unfortunately you would need to remove the paint and prep again to get rid of this and redo the paint. If you decide to do that make sure to clean with something that also degreases and rinse very well to make sure no residue from the cleaner remains. On chairs and kitchen cabinets it's often oils that end up causing the problems. A lot of people will recommend cleaning more than once to be positive that you've gotten everything - even going as far as 'stripping' if there is a finish or years of buildup.
Sorry you ran into this problem and good luck,
Ging

klmeenan-just to give you another's perspective, I don't find that look offensive at all on your papasan chair. Aging on older structures is okay. That yours is done in silver (I think) makes that cracking all the more "time" appropriate. All silver is old too.