I am by no means a tax professional, but have received help from several in the last 5 years regarding K-1 issues. In TTAX Premier, if I go to the line 20 box, scroll down and choose "AH" - without entering any amount - my next screen has "Enter Box 20 Code AH Amounts". Of course, none of the lines shown correlate with anything on my K-1 so I added the AH1-9 codes that seem to be relevant based on the explanation listed by the partnership for each, under "Description and Amount" in the box below. For example, on my K-1, AH1 & 2 deal with UBTI which only involves qualified retirement plans or tax exempt entities - not me, so I don't enter that information.
Also, following "Other description Enter Below" is a "Learn More" link which gives you a vague overview which may or may not help:
"Certain items (generally labeled "Other") on your K-1 may need to be entered in several different places in TurboTax. Consult the instructions that were included with your Schedule K-1. These should tell you the form and line where the amount should be entered, then, follow these instructions:
Enter the form number or name of item in the search field in the toolbar at the top of this screen. You will then be presented with a list of topics that address this form. Select the topic that best matches the description given in your K-1, and then let TurboTax guide you the rest of the way"
