The FIRM 2xx executables are obsolete, and have been
replaced by FIRM 3.0.

To get the current FIRM, go to the ftp site
ftp://ftp.stat.umn.edu/pub/FIRM
and download Firm_man.pdf (the FIRM 2xx manual, which
is still informative on most aspects of FIRM usage),
and firm3_0.zip (an archive containing the current
executable, and an update on changes from FIRM 2 to
FIRM 3.