Setting up auto responder emails can be done even if you do not want to put a name in any of your form fields. If you wish to leave the form field name as blank, you can use the short data field name.
You have to click your form field and on the left side of menu, you can find "Short Data Name Field" on top of Conditional Display. This is where you will have to assign a name to each of your unnamed form field. (ie. Form field # 1 - labeled as Email1, Form field #2 - Email2.... )
After assigning a name to each of the short data name field, go to autoresponders and create a new auto responder. Choose and select the form you are working and you can see on the form fields the name assigned on the Short Data Name Field.