I just booked a reward ticket for Aug/Sep 2012 that looks like:

YVR - YYC: AC J
YYC - FRA: LH F
FRA - IST: LH C
IST - FCO: TK C
ATH - FRA: LH C
FRA - YYC: LH F
YYC - YKA: AC Y
YKA - YVR: AC Y

No problem with any of the transcontinental flights on LH and intra-Europe tickets on LH and TK, but the YVR to Calgary flights are another story. On the outbound flight the only Calgary flight available was the night before, and on the way back I have to go through Kamloops after a 7 hour stopover in Calgary.

The transcontinental flights should be the problem - not the connection between YYC and YVR. Annoying!

The person at Aeroplan was great - said that Air Canada wasn't releasing inventory and they had complained to AC but they haven't done anything about it.