"What should I check to correct K-1?"
You can go back through the Distributions section and ensure that you actually made a distribution, and also try entering the appropriate figures for Percentages and Distribution amounts (see first screenshot).
Enter forms mode and ensure that sections A and B are populated in the Beneficiary's Allocation Smart Worksheet (see second screenshot) and, if not, enter the appropriate figures in those sections. After doing so, you should definitely see Part III of the K-1 populate.
