For me to have my 6 Desktops, I used;

1- Modified hildon home from Matan
2- Homescreen selector widget

With the 2nd I managed to put the check-mark on the rest of the screens I want.
Also if it happens to not appear on Manage views. Then I reinstall the hildon-home .deb 0.3.66 , which I know is outdated but when I reinstall it, I can view on "Manage View" the rest of the desktop, and check them.

Hope this helps!

EDIT: I did a Reboot after reinstalling the hildon-home. Then the other desktops appeared on Manage view.