To include a hyperlink or allow entering text below a form, you must insert a continuos break at the bottom of the form and then go see the task pane go to "View - Task Pane", choose Protect Document from the drop down list.
Then stop protection of document and in the task pane check the Editing Restriction box. Choose "Filling in Forms" and then click on "Select Sections". Figure out whic section you want protected.