In particular I am interested in issuing a DONE4 with open sectors (to overcome LHR/LGW land segment rule)
I don't believe you will succeed with this. It doesn't matter whether it is paper or e ticket; land segments (including city co-terminals) still count towards the 16 segment max.
Other questions. Since I am starting my RTW trip in ICN and purchased the ticket at YVR. When I have finalized my open-dated segments can I get the finalized paper ticket printed here at IAD or DCA?
I think paper tickets still have to be hand-written on the old red-carbon stock (which is why they are a pain to re-issue). You can get an
itinerary printed anywhere.
Can I convert the paper ticket over the phone and/or at IAD/DCA to an e-ticket? OR, do I have to venture back to Canada (or Korea) to do any or all of this?
Technically (and AA RTW desk will tell you this), once a paper ticket, always a paper ticket.
However, it CAN be changed to an e-ticket, if you are face-to-face with a cooperative ticketing agent, AND he/she manages to get a cooperative agent at "tariff" on the phone. I have done it twice in the past year, once at JFK and once at BOS.
Of course, you cannot have any open-dated segments remaining.
Happy Travels.