There are two possible drivers for Enttec Pro.
MadMapper uses the one that is installed by default on OSX (called VCP for Virtual Com Port). If you installed D2XX driver (for instance to update firmware), the other one is disabled. Hopefully there is a simple tool to switch for one driver to the other: http://macdownload.informer.com/ftdidrivercontrol/
Just start it and press the button to activate "Simple Serial" (that's the VCP driver)
Let me know if that's not your issue