i havent messed with those brands but here is some advice. paints nowadays have chemical bonding. never mix brands. it might work with one color ok but not another or even another brand. u used rustoleom primer with moltow paint. i would find out if moltow has a primer and use that. read all of the instructions. there is a reason why they wrote what they did. recoat within xx mins. why? cuz paints gas off also tention. you can screw up paint by not following instructions from the manufacture. Not saying you didnt read them.
I would let it dry for a week or so. maybe u can lightly sand off the cracking and respray or brush it on.