Clearly this guy can "run" for the Presidency. But he is not eligible to hold the office if elected. But that is for the Congress, the Electoral College and the courts to determine. There is always the possibility that if he were elected, the Constitution could be amended to allow for Naturalized Citizens (like Obama) to be president between the time he is elected and the time he is sworn in. I'd say the odds are about the same for him getting elected as they are for the Constitution being changed in the 2 months between November and January.
However, the FEC “was” ruling on his eligibility based on current election law.
My point is simply this: they are wasting everyone’s time by ignoring the constitution to which that election law must adhere.