After entering data and completing the "mortgage insurance" portion of my rental property income page it still says that I have not started that portion. Why?

Did you click the box and enter the amount in the box that appears?

Qualified mortgage insurance

Qualified mortgage insurance premiums are those paid or accrued in the current tax year for mortgage insurance in connection with a mortgage used to purchase your property. The contract must be made after December 31, 2006. 

Qualified Mortgage Insurance means:

•  Mortgage insurance provided by the Veterans Administration
•  Mortgage insurance provided by the Federal Housing Administration
•  Mortgage insurance provided by the Rural Housing Administration
•  Private mortgage insurance (PMI)

In order to be deductible, mortgage insurance must be paid in connection with debt used to purchase property.