Windmill is spinning after loading a save even if it was previously been stopped by the lever. If gnome is still not saved then he is rotating with a wheel but his ropes aren't:
https://nosferatu.g0x.ru/pub/.bg3/windmill_not_saving_state.mp4

Also ropes could be not aligned with gnome body even if windmill wheel is not rotating:
https://nosferatu.g0x.ru/pub/.bg3/windmill_ropes_not_aligned.mp4