You've got two possiblities. 1. Sending back. I think TS won't refuse, if they do let us know.
2. Keep it and try to get straight into the things. This scope is a very fine demonstration tool for its assembly is so easy and obvious. You can dismantle everything and reassemble without the danger of irreversible damage. These scopes seem to have some issues described in the 50 foregoing pages but your scope might be a very special one we all could possibly learn from it. As you described until now with a wiggling primary baffle (it is not the finderscope ) I'm afraid your next logigal step would be removing the buttplate from the tube which is again very easy by just unscrewing 6 (or 8? for the 8") small screws on the rear circumference and check if the center baffle is moving or the mirror can be turned like an old music record. And pics from any position might help. Disassembly, taking pics and reading dimensions can be done, unlike stargazing, without a cloudy sky in a cosy room at daylight No big thing, but if that's not your business, back to 1.
But if you continue and it really turns out that you get sort of an image way behind extension rings, diagonal and eyepiece threre're two possibilities: The distance between the mirrors is too short. (1 mm short needs about 16 mm more backfocus). spacedude can tell the exact data I guess for I own just the 6 inch scope.
If you find the mirror distance to be correct and you still find an image at a way too long distance one or both mirrors are mismatched. This would be then your last exit chance for another scope, I suppose.
I was just considering my experiences and mentions in this thread and advising along propability
loose mirror - often
odd assembly - none
wrong or mismatched mirror - none
Edited by quilty, 11 October 2020 - 04:19 AM.