Cross winds lifting the panels: In the first picture you can see that the bottom of the raised rail is so well sealed that water only runs off the roof where there is a small gap in the rubber seal. Maybe when tilted up a cross wind could be a problem...note to self, do not tilt up in heavy winds. It would be fairly easy to run a cord through the grey tank vent and over the ends or the mounting boards using a eye bolt at each end (screwed into the roof) to hold them down when raised.
To tilt up I have seven 20” long notched wooden 1X1 that clip on to the panels. I’d rather not drill into the roof so I’m going to see if hold downs are really necessary.