DEFAULT <other non-related DISK IGNORE rules> DISK %^/archive[0-9]* IGNORE DISK * 90 95
I know technically the "DISK *" should probably be "DISK .*", but I thought that's how it was by default.
Am I just wrong with my PCRE?
Try this: DISK %^\/archive[0-9] IGNORE
P.S. Your main problem was not escaping the /