I think there us a discussion in the "setting up your mount" area of the Losmandy G11 mount manual...or else download the manual for the Orion Atlas that also discusses it.??
Basically you have to shim where the scope mounts to the dovetail,? while you rotate the RA by 180 degrees... until you get the exact same eyepiece image at both rotations.? Then you have zero cone angle error....
(For me, it's like drift aligning...I fight against doing it til I realize there is no other way...)
I have read about cone angle and have a mental picture of what it is, but have no idea how I would go about measuring it on my little scope, let alone correcting it. So the answer is no, I didn't...