Hi Paul
Although I have one and used it on my Mewlon 180 indoors, I found it easier to collimate outdoors on a real star so unfortunately I don’t have any real experience.
Here is a photo of the Tak collimating scope on my Mewlon and an MS Word doc I found somewhere along the way.
I think that I found that using a 2” adapter with a grub screw would slightly shift the concentric circles hence the (Japanese language) pamphlet that came with my scope appeared to show the use of threaded adapters.
I think that there is a collimation video on the RCOS website at:
http://www.rcopticalsystems.com/support/resources.html
Cheers
Dennis