Thanks for your reply.

I (re?)did the installations you adviced me.
Then, I reinstalled Tonescape from scratch.

I still get error messages. First during the installation I get the
message:
"Your video adapter may cause the application to run slowly"
Then, i get plenty of error messages and Tonescape crashes due to
DirectX related issues...

Thanks for helping me, I really would like to use Tonescape. I read
something about the incompatibility with Dell video cards...

Alessandro