Try this....
Delete your WASM folder.
Load onto an active runway (engines running, ready for takeoff).
Sit there for a minute or two and let everything initialize.
Go back to Free Flight menu and load your flight as you normally would (at gate, ramp, etc.).
Click Fly Now and go about as you normally would.
If you are getting the birds eye view of death upon loading at a gate, somebody on this forum suggested the following:
On the Free Flight screen, select your airport and departure gate as you normally would
Zoom way out....
Click "Fly Now"
I had similar problems to what you were describing and this seemed to have taken care of it for me. Report back if this works for you.