Make sure there is no pressure in the bladder . fill the inner chamber and push the damper rode in and out a few times to get rid of the air under the mid-valve piston.
Now fill the chamber up until oil will overflow when you install the bladder assembly into the top of the chamber. (the damper rod must be fully extended at this point before you put the bladder in ) tighten bladder asssembly into chamber cap.
Now remove the allen screw on the side of the upper chamber , this will let out any excess oil . Re-install the screw.
Refill the bladder with 1.6 Bar N2
It should fully extend .