Chaos83p, have you already recorded in Cubase with an older Axe-Fx ?
Monitors from the axe output
Usb cable from the axe to the mac
In the mac preferences, select Axe-Fx 3 as audio device for input and output (maybe the wrong terms as my computer is not in English).
This should be ok as you can listen to iTunes music on your monitors via the Axe.
Then launch cubase.
Open a new project
In the connexion audio window, input page, add a bus.
Stereo in 1 L and R. For them select In 1 (Out 1 block L) and In 2 (Out 1 block R)
In the output page, for stereo out, select Out 1 (out 1 L) and Out 2 (out 1 R)
Create a new stereo track.
Open the « explorator window » for this track and select stereo in as input and stereo out as output.
Press the Rec button of the track. Press record in cubase and play.
What you hear is the sound from the axe, not what you’re recording.
You should see meters going up in the stereo in meters and the wave form drawing in the track.
Press stop. Make sure your track and stereo out are not muted.
Then press play and you should hear the (wet) track you’ve recorderd.
Sorry for my bad english.
This is a simple setup that should work as it works for me.
If there is a step that need more precision just tell.