2) No, it won't change anything other than that income would be taxable. The excluded Foreign Earned Income would likely put your taxable income into a higher tax bracket.
3) No. Pretty much the same answer as #2.
4) Yes, TurboTax should be able to handle it. Just be sure to maximize the 330 day Physical Presence Test by choosing the best 12 month period (such as September 2017-September 2018, which puts more days into the 2018 year).
