Supported since: FL Studio 8.
IMPORTANT (especially for the MIDI-cable version that's not auto-detected): To set the feedback up properly, in the MIDI settings window, set the INPUT and OUTPUT port numbers to the same value. This should be (untested) automatic for the MCU Pro (USB) version. NOTE: On FL Studio 8 to 10 you MUST use port 102.
After setup, please make sure that Options->Enable MIDI output is checked, so that the MCU is getting feedback from FL Studio.
The support -may- work for other controllers using the Control Universal system.
Further discussion here.
Functionalities explained here:
and when you have it set up correctly what you can expect...