No procast locks HN for you after some time (to avoid procrastination, as the name suggests ;). Max visit is the time you allow yourself on the site (starting on the first visit) and minaway is how long it is blocked. It's in minutes, iirc
No problem :) It can actually be pretty useful sometimes, even though I have it disabled right now. You can also use it as a "spree breaker" by setting the values to something very low, like 60 visit/20 away.
I'm guessing they are documented, but I'm too lazy to find/read. ;)