We run Tues. and Thurs. nights ~7-midnightish EST.
You get points for doing just about anything that positively impacts the shell (ie showing up on time during scheduled runs, getting pop items, helping kill gods, etc..)
We don't penalize people for missing. Our core group doesn't mind doing the farming it seems, but we would like more people to help kill gods, so if you can only make it one night or would like to just kill gods and skip farming, that's no problem. Obviously the people who help the most get the most point and will get to bid on items sooner.