you need to load it twice because the first time your loading into pastacfw to disable signature checks, if you try running FBI first it will just fail to install any non signed cia files, so once pasta CFW is loaded you can then go back to FBI via CN and it will allow installing unsigned content, you only need to do it the first time once you have FBI/BBM installed to the homescreen you can just use that instead^btw why u relaunch cn again?. afaik u just need to load fbi and install cia.
i will try once i get back from work.