[RedP85]

One of the links at the back of the spiral ropes is most certainly broken.
Common issue now.
You can buy replacement parts at 3d-gem.com
and follow the repair process by John here

 

[RedP85]

Any idea how long the clips and epoxy hold up with this fix?

They are avail only since 1-2 years..

 

[RedP85]

Theses are THE known problem with the sunroof. Nothing else is recurent, nor common.

 

[RedP85]

Possibly you are one tooth (one spiral of the cable) off at the motor gear.
I would remove the motor, reposition the sunroof with driver side a tiny bit forward, and try again.

 

[RedP85]

I think you are at the max you can get by left/right : the orientation of the cable when glued to the new part will dictate how much the 'one tooth' can give.
I think what you have left to do is shims, but be carefull not to raise too much.
You don't want the sunroof to be scratched when sliding in.

 

[RedP85]

Sorry, can't help anymore, won't give you a thinkness.
(even if I have an idea from looking into my car)