I sold a rental property last year. I owned it more that 5 years. Does anyone know if rental properties are part of the "qualifying Oklahoma property" that is not subject to capital gains for state taxes?

No, you should not need to enter any passthrough entity information.  The same is true for the Federal ID number.  You have the option to enter an ID number if you are a passthrough entity or the OK location of the property.  

Assuming you have a capital gain from your federal entries in the "Wages and Income" section you can follow these steps.

1. Edit/Continue your OK state return
2. Continue through the residency questions and sale of Government Obligations page
3. Answer "No" to the Gains/Losses from Passthrough Entity question
4. Continue through to arrive at the page titled "Summary of Oklahoma Capital Gains and Losses"
5. Edit the "Land sale" item
6. Put in the Ok address for "Location"
7. Blank out the "Federal ID" box
8. Select the "Real Property within OK" option
9. Continue
10. Done
11. Continue (even though the page says you may be missing information)
12. Continue through the rest of the OK interview

In online versions you can view the OK tax summary with the steps below.  In desktop versions use the forms mode to view the OK form 511.

The OK Adjusted Gross Income will reflect the subtraction of the land sale gain.