Projects created with PLAXIS 3D AE or PLAXIS 3D Classic that contain custom connections will encounter problems during the regeneration of the staged construction settings in the PLAXIS 3D 2016 version.This problem occurs both with custom connections between two plates and between a plate and a beam.
As a result, an access violation bugreport appears when trying to switch to any of the green modes (Mesh, Flow conditions, Staged construction).
This issue is now fixed in PLAXIS 3D 2016.01
For PLAXIS 3D 2016.00, this work around was available in order to be able to continue working in the existing project :