There is certainly likely to be no correlation between Asperger's/Autism and Acne, except in maybe those cases were certain individuals fall behind in hygiene or poor dietary habits.
I had horrific cystic acne starting around 13. I was complacent with the situation but my mom just wouldn't let up. After being bugged, and bugged, and bugged about seeing a doctor and going on Accutane I fanally caved "f**k, ok lets go". Maybe it would have been different in my perspective if I was smaller, I was never picked on in school because I was much larger than the rest of the kids, even those a few years older than me, and was always considered as the 'scary' guy even though I never was mean, at least not that I was aware, I recall being told all the time that "you always look anrgy". I was 5'10" by sixth grade, 6' by eighth grade and 6'3" the end of ninth.
I took the garbage for about a year, the highest dose possible. The acne went away, and never came back (I still get cysts on my ass and scalp to this day) and now I am sure I have IBS as a result, although it could be the Asperger's that is the culprit for it I am finding out. I was also chemically depressed while I was on the medicine, and had episodes of suicidal thoughts. I resent being pressured to go on the medicine, as my Dad's acne cleared up and never came back as well, without the horrific Accutane.