The numbers for the timers are seconds, a typical ring cycle ring on and off about 4 seconds so for 4 rings set the timer to 16-17 seconds.

As for the ACD there are two ways the ADIX will determine who gets the call, by agent answering priority then by the longest idle. Agent priority is class 20 item 4. if it's a 1 they will get first priority and so on and so on. if everyone is the same priority it will decide just by who's idle the longest..