Digital BW, The Print

I've installed the MIS variable mix inks in my Epson 1160 printer. 
I'm trying to load the Paul Roark curves for these inks. However, 
when I open Photoshop, select curves, select "Load" and enter the 
file name (1160pc.zip) I receive a message to the effect that this 
file type cannot be used with this version of Photoshop (Photoshop 
6). I don't know whether this message means that zip files in general 
can't be used or that this particular curve file can't be used. In 
any event, if anyone has any suggestions as to how this curve can be 
loaded with Photoshop 6 (or can confirm that it is simply not usable 
with Photoshop 6 or can provide access to a different curve for the 
variable mix inks) I'd appreciate hearing from you.