Finally..
Just to share with you my happiness.
I'm seeing now my brightsign working with demo pacakge.
I used a SANDISK ULTRA II 1GB (10MB/sec read, 9MB/sec write) and a very economical TRUST Mouse M2650 Optical Micro Mouse.
It's working very well.
Unfortunately today It's little bit difficult to found an RS232 Cable to use the BrightSign shell. I hope to found an USB to RS232 adaptor.
Then I will to thanks to all the people who helped me during this first step into Roku World..
Ciao
Giuseppe