Mhe failure for manifold constraints

User Questions
1

error: ocp_nlp_constraints_bgh_compute_fun: not implemented yet for nz>0,
For MHE problem, I tried to exert state constraints (on manifold, such as ca.dot(q,q)-1=0) for all stages, but it seems only terminal constraints can work, otherwise the above error appears

2

Commenting to follow along, also worth having a look at:

Moving Horizon Estimation for Inertial Motion
Tracking
Algorithms and Industrial Applications

Fabian GIRRBACH

specifically section 5.2 discusses quaternion and options to stabilize it.