There is a special lubrication for locks. It is a graphite based lubrication (graphite in alcohol in think, no oil which will attract and hold dust). If you go to a hardware store and ask they should have it.
I have used this on house locks in the past and works amazingly well
You could be having a bit of both problems- dry ignition and twisted key. At different times both of them have reared their ugly heads and caused my ignition to refuse turning or be difficult.
FWIW, when I've twisted the key by attempting to release the seat it's almost always been my frustration instead of the seat. Unless the cable is mis-routed or is not adjusted correctly the seat latch will reliably release but it doesn't always DO exactly the same thing! Sometimes it sort of "jumps" a little, other times it just sits there. I've learned to pull backwards on the bottom rear lip of the seat as my best method of removal AND avoiding whacking my knuckles!
And the Lock Ease is a MUST have for all garages, the Duc seems particularly prone to getting sticky.
this may double post but i am gonna say it again anyway, as its not showing my reply
i use triflow on my mtn bike chains, hadnt thought of using that in this application though. i went ahead and bought the graphite and used that. seems to be moving better but there is also a hang up on something.
i may be calling ducatiseattle about warranty replacement soon.