To make the gasket 'compress' more at the top is difficult. It is not easy to movethe hinge position.
However, in the 'corner', cut a 45 degree corner with a SHARP, NEW razor blade, repeat on the other corner so the ends meet up as a "corner joint" similar to a picture frame. Then, using the 3M black gasket glue, carefully apply to the joint. Press and hold together as the glue directs.
Now, the 'new' gasket should not be as compressed as original and should compress a bit when closed.
TIP.. I put Saran Plastic wrap over the corners then closed the window on it.. =) working for 5 years.
If you do not get 'compression' of the gasket, there are other steps ...
Peace and Blessings..