The adhesive available at General Motors for factory windows will not pull out. Far stronger and safer than screws. Think the pull of Devcon (JB Weld) with the flex of silicone. Serious freaking stuff. I would not be afraid to put body panels on with it. It might look and act like RTV, but it's not.
Unless you have a big enough oven to curve it, you will have to come up with a way to use alum extrusion or tube to hold it's shape, or it will be very tough to hold in place while the glue cures, and it will reduce the strength a bunch, being "pre-tensioned" while the thermal expansion goes back and forth.
I wouldn't want screws on the track either, so while they didn't explicitly say "no screws" using them would defeat the entire purpose. They know when a window blows out, they don't know when a screw falls out.
I think the best, cheapest, and fastest solution would have been duct tape, but it's not pretty.