The difficulty of pushing the ceiling panel into the 3M Dual Lock, was solved by using the van's hydraulic jack and a stud, to force the Dual Lock together. After two weeks, I'm sure it will stay together; the next step will be to install the supporting sideboards.
The remainder of the ceiling (above the kitchen area), receives a similar 3/16" plywood panel; but instead of the Tweed, I use a Marine vinyl, that is better protected against the moisture, produced when preparing food in the kitchen. Finally, I use a narrow strip of plywood, covered with the Tweed, to hold up and cover the area where both panels meet.
Video Link
Van Williams