Thanks for your reply!
I have attached a simple example.
It contains two very short scripts, test.tcl and test.do, each containing only one "puts" command. I called each of the scripts with "do" and with "source". In all four cases the text output appears in the CMD window. See the screenshot included in the attachment.
Maybe it has something to do with the message "couldn't open "transcript": permission denied" that appears after Questa is opened?
Why does Questa Intel need this CMD window? I don't know if Questa full version has it too, but we are working with ModelSim PE and Altera/Intel Edition for many years, and that window never appeared.