1) To save for transfer to the PC: you have to have a USB stick installed in the "To Device" port. Preferably a listed compatible one and with enough room for a small MIDI file - not corrupted, etc. Without a USB stick - Montage has no place to save your song (MIDI file).
2) [PERFORMANCE] (HOME)
3) Press the round circle (record) button under superknob - grid of 3/3 buttons, it's the second row - first column.
4) This will "snap" you to the MIDI record screen. Press play to start recording. Click may or may not start depending on your click settings.
5) Press stop (square button in this grid) after mashing down on some keys so they get recorded into a "song" (MIDI)
6) At this point, your song should be saved as "NewSong##" with ## as the next available number. 1, 2, 3, .. 24, 25, ... etc. Songs are saved to internal memory - but you can save a MIDI file if you followed step 1 (to the USB stick).
7) Touch (screen) the song name. You can rename the file so it's easier to find on your USB stick (and on Montage). Type in a name that makes more sense to you than "NewSong##".
8) Far right of touchscreen near the middle is a box "Save as .mid file". This option is only available if you have a good USB installed (step 1). Press this.
9) You are shown a new screen which has the option "Save as new file" - touch this
10) If you renamed the file in step 7 (which you should, so you can keep track of what you want to delete off Montage's internal memory later) - the name you changed to will be populated here. So you can just press "Done" (lower-right) on touchscreen to save to the USB stick

That's all there is for storing MIDI (non-audio) songs.

After saving to USB - you may want to clean up after yourself so you don't end up with 20+ "NewSong" files (like me) or sensibly named files (like you) cluttering Montage's internal memory and song list. I personally have no idea what each one was recording - should have labeled them.

To delete (internal memory):

1) [PERFORMANCE] (HOME)
2) [UTILITY]
3) Touchscreen (TS): "Contents" -> "Data Utility"
4) TS: "Song"
5) TS: touch any song to rename or delete. Wish it would start playing the file when you touch it so you can preview and maybe rename if you recognize what's playing. But if you fail to give a sensible name - you'll need to go back and forth between this screen and the Recorder/Player and use the play button to listen to the file (maybe write down which "NewSong##" you previewed and what the new filename should be) then get back to this screen to rename or delete if you can safely discard after saving to USB.

Side note - you may want to just stick to the recorder screen if all you need is to rename files. Since you can load from that screen and rename. Doesn't make sense to use the [UTILITY] rename feature without a way to preview ("audition").

Hi if your question is how to have a recorded audio from Montage to the usb stick connected on Montage USB to device port, you are on the wrong way, simply because the audio record is done directly on the usb stick, you do not need to "store" cause it's directly done on it.

Plug your usb stick on the usb to device port
Go to play/rec > audio
Press Rec button, it flash (stand by for rec)
Press play to lauch the audio recording.

it record directly on the usb stick.

Jason,
Thanks as always for your very detailed repy but as Joel pointed out, tt was Audio files I was asking about not MIDI.

Joel,
Thanks for that - I hadn't looked at the USB drive after recording. I can see that the files are stored directly on USB. And in order to create a new audio file, I click on the "Audio Name", select "Load" and then "New Audio File" - I hadn't expected to see "New Audio File" under load, which is why I was getting confused.

Sorry about the misread, Sean. I initially read this wrong:

I don't see any buttons like the "store as .mid" on the MIDI tab.

Read it as "I'm in the MIDI screen and do not see a store as .MID option". Rereading - I see how off the mark I was. I think I was coming in thinking I'd already (in the other thread) run through the audio record summary - so I'd round it out with a MIDI record. But that doesn't help when your question is clearly audio - not MIDI. My mistake.

Audio doesn't allow you to record unless you have a MIDI stick and will just start dumping content to the stick. As mentioned - click on the name to rename it so it makes sense to you instead of the default filename.