First you need to get ftoolapp from http://www.flastools.net.
Next you will need to put the file you want to execute in a folder called fscommand which is in the same folder as your flash projector. you will need to put the ftolapp.exe in the fscommand folder also.
Next you will add this command to the button that will launch the file.
Code:
on (press) {
fscommand("exec", "ftoolapp.exe" add chr(9) add "YOUR FILE NAME HERE");
}
Notice you don't specify the fscommand folder as part of the path. Flash 6 will do this automatically.
add chr(9) add
is just to simulate a space to the windows command line.
BTW: If you need to locate files in sub folders of the fscommand you need to use double backslashes in the path instead of single backslashes.
Hope this helps. There is a lot of documentation for the ftoolapp on the flashtools.net page. I will keep an eye on this post incase you need assistance.
Good Luck!