When using fukpsn0.5 you should be using the cert27, Probably best if you start from scratch again (I did this to get it to work). Search the forum for the cert backups and grab them, then replace cert24 and cert27 with the fresh backup ones,
Now replace the cert27 with the fukpsn cert27 (i used comgenie file manager), Then set your primary as your computers (Which yes you probably do have that correct) and then have your secondary as 0.0.0.0 (thats google).
Alright now make sure your ps3 it off, start up fukpsn on your computer, have nothing else running, then start up your ps3.
I follow that start up procedure everytime and have absolutely no trouble. hope i helped