As a foil flyer I would recommend that if you do a dead downwind launch then consider turning the kite and flying low to the side of the window rather than straight up.
It's way safer because the kite never gets high and there is no risk of lofting. You can also run a bit downwind to get the kite to the edge quicker.
The Crossbow guys talk about attaching a weight to the chicken loop (a board or a sand bag or something) then positioning the kite on its tip at the side of the window. Sort of a self-assisted launch.
Excellent advice Greg. I forgot to mention that.
I also used the method you describe but instead of a sandbag I just used
a stick in the ground to hang my loop on. You could use anything... just
attach a leash to something heavy and clip your C-loop to it. Set up the
kite in the launch possition and it just sits there with very little pull, even
in very strong wind. Walk to the bar and launch it. You can land it the
same way. Very safe and easy. No risk of a self launch with crossed lines.
I think Ed's situation is different though, and his beach runs parallel with
the wind direction, so a 90 degree launch angle puts him in the water. In
this situation, you could hook the loop to something on shore, and walk
the kite out into the water and set it up in the launch position. This way
you are launching with the kite over the water, much safer. Just a thought.