Hi Eric,
Sounds like you are putting a 2" barlow in the 2" adaptor THEN the 1.25" adaptor and a 1.25" Eyepiece?
You shouldnt need to do this to get focus. Having said that, obviously with 1.25" eyepieces, this would be the only way you would be able to use the barlow with those.....
I think you mentioned you had a 30mm 2" eyepiece. With the mirror now moved up the tube as per my instructions, this should easily reach focus now without the barlow??
Keep in mind also that as you have a collapsible dob, you can slide the secondary cage down a mm or three to bring the secondary closer to the primary to achieve focus, but with the primary now higher, you shouldnt need to do this with the 2" Superview or the 2" barlow or any other 1.25" eyepiece at all anymore.
Yes, you are right, the best design would have been that the focuser tube was the size of a 2" eyepiece so the 2" adaptor wasnt needed, but hey, what can you do, probably designed by a committee! As they say, a cow is simply a racehorse designed by a committee......
Good luck with it all.
Cheers
Chris