I lubricate the rubber seals using a silicone spray.
As an experiment, I'd also try some talc on the seals. the silicone is part of the annual maintenance, but do not expect the dealers to do this, even for the $800 !
The trunk hings pivots are nearly inaccessible, i think, this, and the hood hinges are seldom a problem.
I had the trunk lid lock tumblers "seize" on me as well. Dirt and soot work their way into the very close tolerance areas and the key lock operation slowly becomes too hard......
Carburetor cleaner and lock-ease do the job..
Hope this helps:cheesy: