That's the lift capacity adjustment knob. It's used to adjust friction on the tube. Unless you get the length of the screw exactly right (down to the MICROmeter) to get the tension right and tighten it up completely for structural purposes for the EAF, it's not going to work. And then it won't be adjustable.
I've seen a few solutions to the Moonlite and EAF:
1) Lots of strong velcro (that 3M Dual Lock stuff) for the bracket.
2) Completely removing the Moonlite housing, drilling a couple holes, threading the holes, and using the new holes for the EAF bracket.
3) Mount the EAF on the rail holding the telescope with some custom brackets.
I've held off, waiting for a true solution. Though there is a lack of structural mounting points on the Moonlite. :