I use my montage as my audio interface for all the internal montage sounds and connectivity to my DAW, thats great, but how do I use the Montage Audio Interface with an external instrument? ( line or Mic input) and record onto my DAW. I can get audio through the Audio In but cannot route to a chennel in a performance.

A Performance is made up of from 1 to 16 internal synth Parts plus an Audio In Part.

The Type of audio Input is a global setting. Press [UTILITY] > “Settings” > “Audio I/O” > set the “A/D Input” to Mic or Line.
Mic is for a low level signal like from a dynamic microphone, guitar or bass.
Line is for a professional output level like from another Keyboard or CD player or audio playback device.

You have an option of setting up the A/D Input separately (one global setting applies for all Performances) or you can setup so that each Performance can be setup and the A/D Input Routing memorized.

_The GLOBAL setup is great when you want the microphone or external device independent of what your doing with the MONTAGE. Touch “FX” top center of the screen... find the Global A/D On/Off
_The setup that you want to use is where you program exactly what happens with that input for each Performance; this allows you to setup and use the MONTAGE’s signal routing, and setup differently for each program... different effects, etc., etc.

Your goal is to setup to use the external device to record to your DAW. We have a basic setup article for Logic Pro users.
Please see the following for the basics of MONTAGE/Logic Pro X setup....
Connecting MONTAGE and Logic Pro X

Assigning an A/D Input is the same as assigning any internal Part:

Call up the Performance you want to work with.
From the HOME screen:
Press [EDIT]
Touch “Audio In” > “Mixing”
Here you have a screen with both Analog (AD In) and Digital (USB In).
Paying attention to the AD In:
set the “Input Type” = Mono or Stereo (if mono from which Input jack)
set the “Volume”, “Pan”, “Direct Level”, “Var Send*”, “Rev Send*” and “Output Select”
* Var Send and Reverb Send are available if you route the Output Select to the “Main L/R” only.

Under “Audio In” you have tabs to let you determine “Routing”, “Insertion Effect A”, “Insertion Effect B“, and it’s own “EQ”

These settings are found in each and every Performance and can be stored as apart of that Performance. They determine where your incoming signal is routed. You can assign it its own mono or stereo USB bus to your DAW. When using the MONTAGE as your Audio Interface tapping the “Output Select” box will open your routing Options for both analog and USB Outputs.

If you are using the MONTAGE to control this external device via MIDI and you are returning audio from this same device to the MONTAGE, then you can treat the external device in a similar fashion to how you treat an internal MONTAGE synth Part.

What that means is, you can setup one of the eight KBD CTRL Part slots as an external Zone. This is where one of the active KBD CTRL slots is set to NOT trigger an internal MONTAGE Part, but is set to Transmit Out via MIDI, only. This will give the same type of control you have over the internal tone generator including controlling its volume, Pan position, and giving you control over its Insertion Effects, and you can even morph to it with Super Knob assignments. This routing situation makes your external synth apart of the MONTAGE Motion Control Synthesis Engine... it can be used as a modifier... and for all intents and purposes you can treat it like it was a MONTAGE sound!

This is covered in depth in the following article on ZONE MASTER.
Mastering MONTAGE: Zone Master FAQ
The following is an excerpt from this article:

Are there advantages in routing the audio output of my MIDI 'slave' hardware device through the MONTAGE A/D Input?

Yes, there are several beyond just saving a couple of channels on the band's mixer:
__ You have an [A/D Input On/Off] switch available on the front panel. If ever you need to cut audio for the external device you can at the touch of a button. Great for those "on-the-fly" type users.
__ The A/D Input "Volume" can be pre-set and controlled on a per Performance basis. Balancing volumes of internal and external slots for complex layers and splits, can be stored and accurately recalled; Realtime control over A/D volume can be assigned on the Common/Audio level of editing in MONTAGE and varied via the AssignKnob/Super Knob system... meaning you can morph and crossfade between internal and external sounds same as you do with the internal MONTAGE sounds.
__ The A/D Input can be assigned it's own dual Insertion Effects per each different Performance. It's signal can be merged with the MONTAGE to the Main L&R Outputs or can remain discreet and travel to the Assignable L&R Outputs. Parameters of the Insertion Effects dedicated to A/D Input can be assigned to realtime Control same as any internal synth Part.
__ The A/D Input can be used as a modifier (modulation source) within the Motion Control Synthesis Engine. The A/D Input can be routed via the MONTAGE's Side Chain Modulation feature to the Compressors, Dynamic Effects, Vocoder etc. adding a new dimension to your musical performance.
__ The A/D Input can be used as a tempo source for all clockable functions within MONTAGE. Great if your external device has any kind of automated rhythmic functions. By setting MIDI SYNC = "A/D IN" MONTAGE will sync all clockable functions to tempo it derives from the audio source connected to the analog inputs.
__ The A/D signal path takes advantage of Yamaha's high definition audio path, VCM processing and Pure Analog Circuit output. It will sound great!