Hey PMDG. I just tried to fly the route from egkk to eham again to see if there still was a problems with freeze(the NGX Toturial 1). I followed the plan as Said in the toturial and right before takeoff I Think i would go to the fmc menu instead of showing the legs. And suddently no freeze at all(the sim used to freeze right after take-off). I was flying a while before I tried to go into the fmc. And the moment i pushed the fmc Button in the fmc menu the sim freezed. I hope i might help you to solve the freeze problem.:)
The same problem happent to me too. If I just fly around with no plan, everything goes fine. But when i tried to fly the plan that followed with the pmdg737ngx(NGXTutorial1) it all frezzed right after take-off.