I have configured a simple test approval form to route a document to the manager. Neither the admin submitting the form nor the manager have named user licenses. In configuring the User Task in the process modeler, I specified the LF user account of the admin staff who would be submitting the form, then attached her email address via the Web Admin Console as directed in the help files. I also included my own user account/email (and I'm an admin and have a named user account). In "Notifications" I checked "Email task participants...".
For testing, I submitted the form and while it shows up in my Forms Inbox, neither myself nor the other staff member received an email notification.
In reading through other Q&As it seems that for anyone who doesn't have a named license, in order to submit/approve/interact with forms, we have to go the Forms Portal route. Is this something different than Weblink? Various answers seemed to suggest that: Forms = Forms itself (named users) and Forms Portal (optional component, participant users).