Sorry, I did wonder about offering an explanation but did not think I was supposed to post on this forum.

In the Function Menu assign SE as the Control and a suitable function such as AUX1 to the channel you wish to use to control camera tilt.

Now create a new Prog Mix. On screen 2/2 activate the mix and set SE as the switch. At the ON/OFF setting screen set OFF, ON, OFF reading from top to bottom. This makes the mix active when SE is in its intermediate position but prevents it from affecting the 100% positions.

Change MASTER to H/W (hardware) and then select LS. Set SLAVE to AUX1 (or whatever function you assigned in the Function Menu).

Return to screen 1/2 and set the two values at the top of the screen to +100. Moving LS while SE is in the mid position will now allow you to adjust the camera’s tilt throughout its full travel range. If you do not require that amount of movement just reduce the +100 values. This will give a finer degree of control as you will still be using the full travel of LS but to produce less camera tilt.