Is the Smaart IO compatible with the Smaart 9 platform?
Yes, though it is now treated as a generic controllable audio interface, like the Roland Octacapture.
You can control gain and phantom power natively within Smaart (View > Input Meters, or default hotkey Shift + E), however microphone sensitivity-based calibration and saving of microphones is no longer supported. SPL calibration must be done manually using a tone generator/calibrator, such as the iSEMcon SC-1.
Gain tracking is still supported; more on that within this article.