Same thing here. Have to use Alt+Tab to exit the simulator. Same problem with all f-4 mods I tried so far (gerritboom, rsvnpilot), same thing with the f-18 mods. Tried downgrading to version 1.2.7 - same problem.
Edit: I did get the F-4E to run with DCS v1.2.7: I only had to re-bind an input key in-game for it to recognize the controls - but after that it worked just fine (goes also for the F-18, only tried DCS v1.2.7). It does however seem to be impossible (for now) to get the F-4E running with DCS 1.2.9 (in-game controls input page keeps showing up completely blank, no matter what I try).
But, in general, yes, it's possible to fly the F-4 : D