How to use Maxx

Hi all,
I have installed the GPari package on my Jornada. It works fine using
its own interface, but lacks command line history.
I would like to use Maxx as front end to GPari, but I am not able to
configure it correctly.
In particular, I cannot understand what I need to write in the command
line field.

I have browsed this list but I have not been able to find useful info.
I have also tried to read the source, but I admit I haven't been able
to understand clearly what I had to do :(

Anybody can help with a short howto?

Thanks a lot in advance