Title should be: Can NOT get to show subitems of mainmenu in Pixture Reloaded

I installed Superfish on Drupal 7.9 and Pixture Reloaded. In Garland the submenus of my main menu show up, so I would say Superfish is working.
But when I switch to PR the submenus do not show up. I searched and tried a lot of options, but I only managed the main menu to show up.
In PR Superfish is placed in the block 'Menu bar'

Anyone an idea what I can do about this?