Your BITalino is not displaying a Bluetooth Function as it should, since the connection is done over Bluetooth, not Serial COM.
Please try this:
- Remove your BITalino from "Devices and Printers".
- Open OpenSignals.
- Search for Devices.
- Click on your BITalino.
- Pay attention for a dialog stating "A device is trying to connect" and enter the pairing code 1234.
Let me know if it works.