Configuration change for Watchguard Firebox 700

I have a problem with a Watchguard Firebox 700 (Model: F2064N). This
system has theree interface: external, trusted and optional.
Now, I need change IP information for the trusted interface because I
changed my network configuration.
Is possible change this setting using a console program
(Hyperterminal) by rs232 or a Telnet connection on trusted's
I know that using Whatchguard's configuration program is possible, but
the original software on media compact disc is unusable because the
support CD is damaged.
Or is it possible download from Watchguard's website a new sofware