Hi Matteo,
here is your solution:
Overlapping of Main window with Footer window in Smart Forms
It is an external link, so I just repeat the major steps in case the link will get lost.
You need a secondary window which will contain your footer information and you need to set the options in a correct way, that it just shows up at last page.
That is made with a small trick. You create a folder, what should show up after everything is printed in the main-window, but because of the positioning is normally not possible you let here show up the secondary window mentioned aboveImage may be NSFW.
Clik here to view.
~Florian