First of all, a special thanks for your answer...
I've already read the FAQ indicated but it didn't suit my case.
The driver works properly only for a few minutes. After that , the program stops and no wheel action (analogic n or digital) appears on screen, even if I am not playing. If I turn first off and then on the wheel, the driver starts working but only for a few minutes.
I don't believe that it is a hardware problem, so I'd like to know where I can find an older version of the driver.