OK, talked to my MD friend and here's what it was - there is a file SY_SQL.pvc in the SY folder (that should not be there - I have about 10 SY_SQL files in there that shouldn't be there) and startup was looking at that to determine it was an SQL installation - it wasn't even looking at the activation key yet! I renamed that file and now it's running on the same keys it had been running on. I have no idea how those SQL programs got in there - they have no mods, and like I said - I think I would have noticed if I accidentally clicked on the Install SQL option instead of MAS90...
Converting files now. We shall see how it goes.