For the mortgage interest - if rental was available for renting for 5 months, then divide and enter 5 months of interest under the rental section only (the other amount of interest will go under the personal section). If the rental was available for 5 month but only rented for 3 month with 2 months of personal use, still enter 5 months under the rental. However, in this case if 2 months of the interest are disallowed under the rental section, then these 2 months of interest will automatically transfer to the personal section (Schedule A).
For the Property taxes - Since all property taxes paid during the year, it really doesn't matter which of these 2 text fields you enter the information into. So just determine what property taxes related to the time you were in either home as your personal residence and put that under main home. The remainder can go under the additional property section. Just make sure the totals in the 2 fields equals the totals for all property taxes paid during the year on all properties.
