hi
please help me

I apply gel coat on the mold ( . but some area I applied more gel coat and these area  is thicker than another area ( some area has  mm gel coat and some area has 1.3mm gel coat. is it possible to different thickness effects on the
de-molding of my part from mold?
if yes, please let me know what is it exactly?

2- if i add more cobalt to polyester resin what is the effect of de-molding the part? is good or is not good?

tanks so much