what is this 'myveg.veg.1.sfap0' - where myveg is my actual veg file?
vegas just started creating these files (about four of them - .sfap0, 1, 2, etc.,) in the middle of an edit - i've deleted them (they were pretty huge, so is the project) to no detrimental effect so far....
Those are audio proxies for embedded projects. When you drop one veg into another, Vegas generates these files so that it can play an accurate mix of the audio from the embedded project. No problem deleting them, Vegas will regenerate them as needed.