I needed a bit of trial and error to find the right way to do the ftp. The help screen for ftp protocols has incorrect and missing information, and the help information here was a bit scattered. Here is what should be noted. My corrections are in ALL CAPS.
Tap Forms has built-in …
To start or stop the Web and FTP servers, simply tap … THE PORT NUMBER FOR BOTH WEB AND FTP SERVICE IS 8080. THE FTP SERVER REQUIRES THAT YOU LOGIN AS ANONYMOUS.
Alternatively, if the ftp port is supposed to be 8021, then my version of TapForms is working improperly (it shows 8080 for the ftp port).