how to fix a squeaky window on renault laguna?

Hi all,

Don't know if any one can help. I have a 54 reg renault laguna estate and the drivers windows sticks and squeaks awfully loud especially in hot weather, I think it is due to the glass becoming loose from its attachments. I have tried to gain access to the window so as to confirm my thoughts however it does not appear to be straight forward as how to gain access and I didn't fancy just riving the door covers off after removing the screws, especially if this is not the source of the problem. If anyone has ideas or suggestions that would be fab.

many regards Chris