Yep! I am in the same boat. Here's the thread. The problem I had was I had to hire someone so it became too costly. The problems were that the software kept smoothing out the sharp edges and making the helmet "sag"....so there was that. The next thing was that he couldn't get the sizing right. He had to print it overtime to see if he got it right and it was costing me an arm and a leg to get it wrong....so eventually he gave up. He tried to make it symmetrical which was his first problem, I told him not to do that. So he never could get it right mostly because he would not listen to my directions.
I can see HT had the same issues..smoothing of the edges and tried to make it symmetrical so the eyes got too far apart, same problems i had. I'm guessing, but I feel pretty sure thats the challenges they faced on the Sandtrooper sculpt.
Here's the thread to see how far I got.
https://www.sideshowcollectors.com/...l?highlight=scan+helmet&highlight=scan+helmet