Ah, that would explain why there are no references to the Bird-Jones design in the current docs, yours is a discontinued design. And sadly, it's a much maligned design as well. I'm afraid you are likely to suffer a great deal of frustration getting decent results. As Kathy pointed out, the recommended practice is that you'd need to remove the "corrector" in order to collimate properly. And that's likely going to require the disassembly of the focuser. Too much hassle in my book. I'd scrap it.
As to what you might still be able to learn, I'd say that sometimes, for your own sanity, it's best to bite the bullet, accept defeat, and move on.
Sure, you can probably fight with it for a while and make it work. But the odds are, you are going to be disappointed with your results, and that might discourage you from continuing. Getting started in imaging can be daunting enough without using equipment that is difficult to work with.
As a "newbie," you'd probably have better success using the Nikon 70-200 2.8 in your signature. Fewer potential issues to deal with. The shorter focal length is more forgiving of poor tracking, so if you are not ready to guide (which you are going to need to do for decent results at longer FLs) you can still get fairly acceptable results. It's also a faster lens, even if you stop it down a bit to improve sharpness. And with a Nikon camera, the attachment should be solid, you'd have no issues with spacing, fit, or other connecting issues since it's designed for that camera. There are still a lot of targets you can shoot at the shorter focal length, such as M31 @200mm FL at this time of year. And you'd be spending more time learning the processing side of the equation and not fighting with the equipment. Then, as you feel you have the image acquisition and processing better in hand, using your 200mm scope on your new mount wouldn't be such a leap forward.
That would be my chosen path at least.