Ken, really nice job on the exit.
I can do that and not even worry about security at my house since the window I would use is on the back of the house on the second floor.....
I have a similar set-up except it is vertical in a (unused) sliding door in our living room. I made a board that sits in the track and jams the slider from opening. You could use the same principle on a window for secuirty.
Unfortunately my house has all casement windows, so I had to come up with an alternate method. I did rig up something in a basement window with insulation board for wintering nucs at one time, but sure not something I would get away with in the house.