<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by snake:
Isn't there a limitation on open jaw tickets that the open segment can't exceed the shorter of the flown legs?</font>
That's what I thought, too, but check this out:
From MileMarker Toronto--HKG 7790, HKG--Moscow 4400 miles, and Moscow--Toronto 4640. So, he's barely meeting the limitation-- I was surprised.

Guess you've done your homework, dominick!!
One problem you may find is that you might not be able to mix NW flights and KL flights in the same itinerary... but if you go YYZ-HKG all on CO metal, you won't have to worry about ticketing....
To find out if the itinerary will work, your best bet would be to call CO and have them price something.
Good luck!!