[gradsusr] Open Error : Can't open description file

[Inoue Kazunori]

Dear Sirs,
I am a new user, not so familir with Unix. I encountered the follwoing
error.
Sanning description file: model.ctl
Open error: Can't open description file

My system is as follows,
Cygwin on Windows 7 64bit
grads-2.0.1-i686-pc-cygwin.tar
grads-2.0.1-i686-pc-cygwin-dlls.tar were installed.
In Cygwin, I started Startx and in X, I can start Grads. In comand
prompt, ga-> open model.ctl, the above error comes. The model.ctl file
is located in the same folder as Grads.exe.
Please inform me some link sna documents. Highly appreciated.

-- 
Inoue Kazunori