I had the same problem... windows
opening while in motion. I solved it by attaching a small / thin piece of ferrous metal to the frame of the aluminum window... behind where the sliding window sits when in the closed position. Make sure that the thickness does not interfere with the opening of the window.
This small (width of the exposed frame... by ~ 3/4 inch) is a "contact point" for a small magnet that we attach on moving days, are easily removed and stored when setup. Hope this helps. Cheers
Example of magnets used