PrintMe Connect stops working when I'm not logged into the PC running PrintMe Connect.

Printers aren't visible on the AirPrint enabled device.
You cannot ping the Wireless adapter IP of the PC running PrintMe Connect.

Solution or Workaround:
PrintMe Connect services will start automatically. However, some Wireless network adapters do not retain an IP address when you aren't logged into the PC. If you have a wireless adapter exhibiting this behavior you will most likely have to keep a user logged in for PrintMe Connect to remain active.