Just an FYI, I had never used the built-in FTP server but I did have it enabled just in case I was not home and needed a file. Was having issues accessing the built-in FTP yesterday so I disabled it and installed your plugin from CA with no success, I was having xhaloz's same issue that no matter how many times I would start the service via the "Start" button it would refresh the screen and show "Shutdown".
I went ahead and tried what xhaloz suggested and it worked like a charm. I recently upgraded from 6.2 to 6.3, not sure if that is why things have changed but it might be something with the new software revision.
Thanks for the help!