To connect the MasterPlus+ software and update the MM712 FW to the latest version, please toggle the bottom switch to 2.4 GHz mode and make sure the dongle is plugged into the PC.
The MasterPlus+ software will automatically read the current FW version of the MM712 when the MM712 is connected in 2.4 GHz wireless mode, and pop out to tell you to update the FW.