GLS, one thing there: I current work on the ATVC and have some improvements for the hydraulics model there. Now, which outputs would you need from the hydraulic valves in the MPS for your engine/MPS model to do its job?
We could then unify the hydraulics over the next weeks and use standard components from the "hydraulics" namespace there.
The ATVC will have only small impact on the SSME implementation, you only need a function to get/set subsystem reference frame (position and orientation) and apply the new reference frame then on the Orbiter thrusters. I will implement this once I am happy with the hydraulic actuator simulation.
The actual gimballing will be handled by a "GimbalMount" class, that has a SSME and two hydraulic actuators as children.
The already started ATVC class currently gets refactored, instead of one big blob, it will now be made of similar modules for SSME1, SSME2, SSME3, SRB1 and SRB2.
The CRTMFD only handles those formats itself, that are produced by the MEDS display. What goes over the IDP is instead produced by the IDP class (and should actually be defined by a DEU program made of 16 bit words, that is updated twice per second by the GPC). Thats all displays that are driven by the GPCs and have a Function+OPS/SPEC/DISPLAY number.