There doesn't appear to be any place to report a bug.

[morton1000]

No radio button to select applying the refund to the next year

[mesquitebean]

Applying a refund to the next year is not done that way or in that section.  Here are the steps, which are not very intuitive:

To apply a 2017 Federal refund to the next year's taxes, try this:

• Federal Taxes tab   (or Personal tab in the desktop Home and Business Edition)
  
• Subtab Other Tax Situations.
• Scroll down to Additional Tax Payments.
• One of the subtopics is Apply Refund to Next Year.
• It will ask you how much you wish to apply.