This key binging is using "Page Down" in default TSW4 settings as well as AWS acknowledge. Therefore everytime you use AWS system ack key it will toggle DRA as well, resulting in a traction cut off while train is running. I think the keybinding for DRA should be just left empty to avoid conflicts as player is only expected to be using DRA at standstill in front of a red signal to prevent unauthorized train movements and can be still operated via the driver´s desk button. By the way, the "Back" button on the UI is not working once you entered the key bindings submenu. Cheers
