QHY8 is a DSLR sized chip and if I recall correctly is the Sony 6.3mp chip first used in the Nikon D70.
So it is what is termed in the CCD world as large format.
This then requires coma correction from your Newt in a circle wide enough to fully illuminate your chip with a fully corrected image. This is referred to as the corrected circle or corrected field. It has a dimension like 36mm etc.
The MPCC per the Baader website will correct even 35mm film size (44 x 44mm I think it is) which is bigger than your chip of 21 x 14mm.
I looked up the MPCC specifications and as pointed out you need to have it set 55mm from the back metal flange of the MPCC
to the top plane of the chip. This is called metal back distance (the last metal edge of the corrector to the surface of the CCD chip).
All correctors/flatteners have a metal back distance. You then need to have the correct length adapter to make sure your MPCC and chip are set at that distance. If one is not available standard you'll have to get one made up. Hopefully QHY sells accessories or Baader does.
There is mention on the Baader site about a T2 system.
Here is the link to Baader's writeup:
http://www.scopecity.com/detail.cfm?ProductID=5515
The unit does not operate properly at the wrong spacing.
Greg.