Dear @Riad.Elhamoud,
Regarding (1), AeroDyn v14 and earlier does not have functionality to support the aerodynamic loading on the tower of a floating offshore wind turbine. I would generally suggest upgrading to AeroDyn v15. As of OpenFAST v4.0 to be released soon, we plan to deprecate the old AeroDyn v14 altogether as we no longer recommend it use.
Regarding (2), I answered a similar question in my post dated Jun 7, 2018 in the following forum topic: ITI 5MW Barge.
Best regards,