A colleague was recently presented with the challenge of dealing with fitting a track up against a pitched ceiling. The garden room had replacement windows running up to the ceiling and the client did not want the track flush to the frames.
For the track to function properly, it needed to be vertical, so a way was needed to create a suitable fixing surface at the top of the window.
The neat solution was to make some small spacers from a piece of batten, shaped to fit the angle of the ceiling. These created a flat vertical surface for the brackets and were pre-drilled so that the screw passed straight through to the rawlplug beyond. The spacers were painted to match the wall.