I just went to www.stewartfilm.com and somehow could not use copy and paste to stick the URL here for a set of instructions that will show you where the adjustments are.

Go to www.stewartfilm.com, click on professional at the left, click on manuals, then choose a model that looks like it might be motorized. I chose the Model A, and found adjustment info and an illustration on pages 12 and 13.

It starts by saying watch out because you can damage the screen if you adjust the wrong end of the throw the wrong way.

The picture will, at best, show you where to look for the screws. You will have to figure out from there whether UP on this Stewart Filmscreen corresponds to UP or to DOWN on your lift.

Contact Auton.