If the custom questions you are using are 'Scale' questions (that is when the customer rates using the scale 0 - 9), the Trends charts will be the same as your core questions and you can read about those charts here.
If you have chosen to use custom questions that are have worded answers such as Yes or No or multiple choice answers such as Daily, Weekly, Monthly, you will still see the same initial Trends charts but you will also see a toggle at the top of the page to help you navigate through the answers.
When you select one answer, you will see the data for that answer highlighted in the other panels which makes it easier for you to focus directly on the results.
From the Store Comparison chart, if you click the blue View List button, you will also have the option to download data via an excel sheet for the specific question that you are viewing.
An excel sheet containing your chosen data will instantly be emailed to your dashboard login email address.