The Add to Menu button is now also available in the Form2Content back-end article manager. After the F2C form is saved the first time (and the corresponding Joomla articel is created) the button becomes active. In the Add to Menu popup you can select a menu to link to the created Joomla article.
23-Feb-2015 : v3.4.0 + J3PRO
Added support for Form2Content (article)