a rom card can come in 2 forms (locked or unlocked)
you need nagraedit4.1 and a programmer set to pheonix mode 3.68mhz
now insert the card and start nagraedit (choose to dump the card)
at this point you will know the rom and revision of the card. it is likely in your case to be rom11 rev BOC
in which case you cannot edit or read the card. to proceed
you will need a modded t911 (xxx.unapit.com) (nexus t911) £30 inc delivery next working day.
you will need the t911 tutorial by chriz2000 from the downloads and a bit of help from the mosc section to flash and use it.
you will winexplorer5 from the downloads
and finally some scripts for unlocking the card.
once done you should then have an open card that reads and writes in nagraedit.
then you will need a prepared au image for your provider (there are some in the downloads that work ok)
load the image into nagra in your case a rom11 au for your provider. edit into the image your ird and bk. now press the write button and it should write the image to the card. the images come with instructions if they are non standard bd keys so just follow the instructions.
finally remove the card and put it in the box - and you should be done.