The amazing PMDG 777 is finally out, however, there is a slight catch - unfortunately, a bug slipped through the cracks. A lot of users are reporting a freezing bug, where they'll touch the FMC mid-flight or any switches then the simulator will hard freeze and won't recover. I've made a post covering the issue here - Long story short it's been pointed down to a "WASM" Issue. The Team at PMDG is working to fix this bug, we'll let you know more once we find out more! Till then it's a lottery - whether or not you'll encounter the bug.