You need to configure the XTC as AUX device in the TM FX instance of your UFX+, then you can control:
- Stereo / Mono
- Phantom Power
- Gain
- AutoSet
- 1..4: PAD
- 5..8: Instr
- Width
- FX Send
- MS/Proc
- Phase Invert (180°) L / R

OctaMic XTC: enable remote control for "MIDI over MADI" in the menue MIDI Sources“:
- Control (Inp.) = MADI In
- USB MIDI 1 = OFF
- USB MIDI 2 = OFF
- MIDI DIN out = OFF
- MIDI ov. MADI = Control

TM FX settings: Options -> Settings -> Aux. Devices:
For the 1.st XTC:
Device Settings:
- Digital Channels: MADI 1 – 8
- Device: OctaMic XTC
MIDI Settings:
- MIDI In: UFX Midi Port 3 (MADI optical !)
- MIDI Out: UFX Midi Port 3 (MADI optical !)
- Device ID: 0

For i.e. 2nd XTC:
Device Settings:
- Digital Channels: MADI 9 – 15
- Device: OctaMic XTC
MIDI Settings:
- MIDI In: UFX Midi Port 3 (MADI optical !)
- MIDI Out: UFX Midi Port 3 (MADI optical !)
- Device ID: 1

Do not enable any other remote control function in TM FX, this is what you need, not more.

See here my setup / settings. Although the article is written in german you should be able to read the configuration part easily: http://www.tonstudio-forum.de/blog/inde … Cber-MADI/

Only for your information, RME also offers a MIDI remote control software where you can fully control the XTC.
But its not possible to run both .. XTC as AUX device under the control of TM FX AND the remote control software.

The big advantage to use TM FX / AUX device is that you can store the XTC settings fully digital together with your other settings in snapshots and workspaces. For this reason I also decided to go "AUX device" and not to use the separate application.