I'm having exactly the same problem with trying to get the "little
plastic panel" off!  I want access to fix the door lock mechanism
though.

I feel a little better knowing that at least one other person has tried
and is having a problem.

Anyone???

BTW Dan, I've occasionally just sprayed CRC, WD-40 etc down into the
compartment through the window hole when the window is down and it's
made a big difference to the winding speed, so I must be hitting
something that need lubricating.  Try and get a spray can that has a
little straw on it to squeeze past the glass.  The first couple of
times I did it I worried that the spray would melt the window tint or
something, but the overspray seems to wipe off without any trouble.  I
also do the runners up the side of the window frame.  I've done this to
several different windows on several different cars and would do it
again before going to the trouble of removing the door panel.

Hope this helps.

Brian