The current PMDG 777 flies beautifully, IF..........

.....you manually fail the PFCs into Secondary Mode via the FMC Failures Menu (there is no other way to get the PFC's into Secondary Mode).     The logic behind is that with the PMDG sim in it's current state, using PFC Secondary Mode will essentially override the current erroneous PMDG autotrim bug that would otherwise be present during flights.     One of the real 777 pilots that participates here on this forum pointed this out a while back and had the original idea of using Secondary Mode in this fashion.   

In Secondary Mode, you need to manually trim the aircraft just as you would any other conventional airplane, and indeed this is the normal behavior of the real 777 as it's Fly-by-Wire logic is designed to mimic conventional control movement input required by the pilot.

You will now be able to beautifully trim out the T7 on final approach and you might just be amazed how stable and predictable PMDG's flight dynamics are when you don't have to fight the autotrim bug anymore.     Also, you will now be able to use the same amount of yoke pressure during all landing flares, whereas with the current autotrim bug the stabilizer can be trimmed unpredictably.     Flaring with the stabilizer out of trim (something you have no control over with the autotrim bug) requires substantially more control force and can result in unnecessarily hard landings.

Try it and see if you don't agree.      All of a sudden your PMDG T7 will fly like a real airplane again and it's a beautiful thing to experience!