I made several flights with the 737 in P3D5.2HF1 and made following observations:

Using the cargo loader can crash the sim and it seems to destroy the Total overhaul mode. The map display is gone after saving the loader.

I had saved my flight after reaching destination. This led to corrupted start situations. Ground power couldn´t be switched on. The switch always snapped back but the power was already on in off position of the switch. The MFD (map) remained black.  It seems starting the sim in default mode, then loading the plane, seems important here, like with complex planes. I wish we had kind of reset button from the sim, to clear all variables. If it doesn´t work, always a restart is necessary :'(