if I may offer a little advise, I've been flying retract equipped airplanes for decades, they are really not that difficult to set up.
for future reference, purely mechanical retracts such as you have are typically more difficult to set up than are pneumatic or 'servoless' retracts.

here's the part that I've seen people miss: with the mechanical retracts physically disconnected from the servo, cycle the gear manually with your hands.
(push / pull on the pushrod) with the airplane / wing upright as it would normally be in flight. this will give you a very good idea of the amount of force the servo will need to produce.
if it's hard to move with your hands, it'll be hard for the servo to move. so first, check and correct anything that may be binding the mechanism.
while you've got the gear and servo disconnected, put a piece of tape on the gear's pushrod and try as best you can to get a ruler next to the pushrod so you can accurately measure exactly how much the pushrod needs to move.
do the same for the retract servo itself, measure how far the servo does actually move when attached to a pushrod.
from here you've at least got a starting point. you could easily burn out a couple servo's (or drain a flight battery) if the mechanics themselves are binding, or otherwise being picky.

do whatever you need to do to make those pushrods as straight and effortless to move as possible first.
make sure the servo moves the appropriate amount next,
refine as required and check again till they're right.

I do not remember the last time I had an issue with retracts not coming down properly
hope that helps.