So, is it reduced air VOLUME to the front, or just not warm?
Also, it has been my experience that when you see a drip run on the screen, it is the result of a leak higher up,where the water drips from the outer skin to the inner, then pools on the top of the window frame and runs to the INTERIOR of the window. I would look higher up on the end caps. Running lights, rivets, or any other seam/river/component mounting hole.
"If the women don't find you handsome, they should at least find you handy." - Red Green