A quick learner from USA says:
September 26, 2016
the balances seem to charge, but as I put the window back in there is a gap between the window and the frame. Just wondering if I can let out some slack in the wood screws or shim one of the sides of the window for a closer fit? The window won't stay in the channel is what I am getting at..
Paul from SWISCO responded:
September 28, 2016
Yes, you can shim in the frame sides to close the gap. Some window models have an adjusting screw in the middle of the window height between the two sashes for this reason. Depending on how long you had these windows, you might have to cut away the caulking to free the frame sides so you can close the gap. Hopefully this helps!