Help Restore from Multiple BKF files

I have a sbs2003 server crash a week after the tape drive died. I chose to back up to disk until the replacement tape drive arrived. I have 55 x BKF files all 1Gb each and I am having real trouble resoring the files on a different server. The backups were created (and tested) using version 12.5, I am trying to restore them using version 11D I do not have a spare server to run version 12.5 on.

Thanks