Hiya, I’ve just upgraded to blender 2.75a from 2.74 (though on testing 2.75 is has the same issue), it seems the extended options for the IK bone contraint have been moved/removed?
On 2.74 the constraint details show up as in the manual pages: https://www.blender.org/manual/rigging/constraints/tracking/ik_solver.html
(note the manual is still out of date as the new Copy Pose/Distance option was in 2.74 as well, though I’ve no idea what it does)
However if I open the same .blend file in 2.75x everything below the Bone option is not there:
Switching back to 2.74 it all works as expected. In either case, the IK still seems to have all the correct settings - I’m making extensive use of stretch and chain length which still seem to be applying on existing contraints, but there’s no clear way to set them on new ones.
Is anyone else seeing the same thing? I’m fairly new to blender so it’s entirely possible I’ve just missed something! Any help appreciated