Screen Capture please. They are showing up for me.
It looks like on this manual page --> http://plane.ardupilot.com/wiki/flying/tuning/
All values are zero and the up/down buttons are greyed out.
I have sections sometimes greyed out for no apparent reason too. Yaw and TECS. Maybe I should look into the source...
An upgrade to 1.2.74 seemed to have fixed the problem.