Question: Max kisses Joshua, so wouldn't he get Max's disease? Or is it only Logan?
C.R.E.A.M. - S1-E5
Question: What was the name of the "group" Max and her "siblings" were in?
Question: This may seem a bit stupid, but I'm new to the show, and didn't start with the pilot: what is that place where Max, Cindy, Sketch, etc. hang out (Where Normal works)? Judging by the presence of lockers, I would assume it's a gym.
Answer: It's their job. They are bike messengers and have lockers to hold personal stuff.
Answer: Max's disease is specifically tailored to work only on cells exhibiting Logan's genome. No one else would notice it.