I installed the license files but AutoSender is still running in demo mode

Make sure to put both license files (i.e. license.txt and license.sign) in the correct location:

on MacOS X this is:
/Library/Application Support/myFMbutler/Preferences/

on Windows, depending on the version of Windows you are using,
either:
C:\Documents and Settings\All Users\Application Data\myFMbutler\Preferences or:
C:\ProgramData\myFMbutler\Preferences (you'll find a shortcut to this folder in the AutoSender application folder)

Once you restart AutoSender it will recognize the license.