The 2.3.5 version of SM2 for Mac is provided as a free download on our website. The actual developer of this free Mac application is Yamaha Corporation. The application belongs to Audio & Video Tools.
From the developer:
SM2 stands for the Studio Manager V2 hosting application, which forms the backbone of the Studio Connections initiative from Yamaha and Steinberg. It is based on open standard cross platform technologies. It is a host/client application, which resides inside the DAW, and hosts additional plug-in editors for a wide range of digital mixing consoles, synthesizers, outboard effects processors and other hardware devices.
You may want to check out more software for Mac, such as GTRC Manager, which might be related to SM2.