Thank you guys so much. Two last questions for you:

1) I'd thought that open jaws had to be round-trip. But clearly these are not:
CAI-IST(stop)-TLV (60k)
TLV-DAR

and CAI-IST (stop and open jaw) ATH-TLV (destination)
TLV-DAR

Are these considered one-way open jaws, and are the rules any different for one-way award open jaws on United than for round-trips?

2) My understanding is that when booked on United one stopover and two open jaws are permitted per round-trip award ticket. Is the following considered one open jaw or two?
SFO-BKK(stop)-CMB (open jaw)
DAR-SFO

If it's only one, could I add a second open jaw on a single round-trip award ticket, such as:
SFO-HKG (<24 hours)-Siem Reap (stopover and open jaw)
BKK-CMB (destination and open jaw)
DAR-SFO

Thanks!