The only conversion Vortex does on the output of <EXEC> is HTML escapement of certain characters, those with ASCII codes from 127-159, most control characters below 32, less-than, greater-than, ampersand and double-quote. This escapement does not happen in text mode (Vortex called with a URL with a .txt extension). Characters 160 and above are not escaped, nor should the escapement of other characters affect their display by a browser. I suspect the content-type of the output is being misinterpreted by the browser, or it is trying to map the characters to a different character set.
Try redirecting the output of dir to a file and viewing that in a browser (with the same content-type/file extension as the Vortex URL), to confirm the display of such characters by the browser.
How are you displaying the result of the <EXEC>? Eg. $ret, <send>, <fmt>?
