No, you are not allowed to amend. It can only be corrected by using Form 3115, which TurboTax does not assist you with that. I highly recommend going to a tax professional that is familiar with Form 3115 to prepare your tax returns this year.
And no, the depreciable amount is the LOWER of (1) your Adjusted Basis at the date it was converted to a rental or (2) the Fair Market value on the date it was converted to a rental.
