Cgi-bin access... re-write issue / feature?

This is not necessarily an Issue or Troubleshooting matter but I have been busy playing with the trial and have taken the plunge with licensed Pro version.

I am busily building and configuring and have only today needed to pull in a non CS-Cart script at, for example: https://www.[the domain name].com/cgi-bin/myscript.php

Nothing! All that happens is I get the CS-Cart ‘404’ page. This is not quite what I expected - to lose all control over my URL access to my time-honoured script location!

Any thoughts? Is this by design?