I tryed removing all the lines, one at time, starting from the last one.
run("notepad.exe")
winwaitactive("Senza nome - Blocco note")
If i leave only these lines (1st and 2nd), running the script gives me back the same error. (CPU usage over 95% and over 150-200-300... (and so on) processes in the task manager.
With the first line left only run("notepad.exe")
I still have the CPU usage "error", but the number of processes remains constant.
Conclusion
Running notepad mess my pc.
you have to Switch "send("!N")" with the last line, but it works fine.
I would like to know why