I'm not 100% sure where I went wrong. The foam might not have been lined up properly to begin with, maybe the weather effected the resin, I'm not totally sure. I did realize that I started in the wrong direction. I started with the top of the helmet and once that dried I moved on to the lower half. Maybe all that added weight caused the foam to shift before I could do the rest. I did it the reverse way this time and didn't have that problem.I see where you were talking about the helmet being warped and it looks like it even twisted slightly. I had something similar to this happen to my chest and back pieces when I put the first resin on them. I used a heat gun and pieces of a wooden stake to untwist the warp. I was thinking if you put some liquor thinner and water in a small container, brushed a light coat over one area and heated it you might be able to save it. I didn't use foam underneath though so I would try this out on a piece of scrap first just to make sure it doesn't eat it.
It looks good so for and good luck!