Just checking (although from what I saw on the Yamaha site I'm pretty sure I know the answer), Is Montage Connect exclusively for Cubase?

No. MONTAGE CONNECT can run inside any DAW that is VST3/AU compatible.

When run inside a particular DAW (meaning it runs as a Plugin), if you SAVE your DAW File, MONTAGE CONNECT (Auto Sync = On) will automatically request a bulk from your MONTAGE, which it will store bundled neatly in your DAW File. When next you open that session’s file, MONTAGE CONNECT will automatically restore every MONTAGE sound and editable setting. This makes finding what sounds go with your DAW Project a no-brainer.

If the DAW you are using is not VST3/AU compatible, you can still run MONTAGE CONNECT as a ‘standalone’ program. It will run along side your DAW. You will need to SAVE the MONTAGE CONNECT data manually — separate from saving the DAW Project. That is the only difference.

The purpose is to create a convenient connection between your MONTAGE and your computer. Any Songs (128) or Patterns (128) that you record, can be imported via the USB connection directly to your computer desktop or directly into your DAW (drag n drop). This saves the step of having to write the MONTAGE Song or Pattern to a USB stick, then shuttling that over to the computer.

Extra Credit: when you create or load data to a MONTAGE Song or Pattern, that data is stored in ROM and can be seen as follows
Press [UTILITY] > “Content” > “Data Utility” > see the Folders for your various Data. As many as 128 Patterns and 128 Songs can be stored on board, in their respective Folders.

Not only Sequences but Sounds…
MONTAGE CONNECT can work as your SAVE one Performance at a time. When you are working with the MONTAGE and a USB stick, you must SAVE all Performances… with MONTAGE CONNECT, you can create a backup of each Performance… giving you a very convenient way to Store and retrieve your custom Performances (and an essential method to keep you “works-in-progress” programming efforts).

Having a file for each Performance on your computer is a safe and secure way to keep your data. It makes it easier to assemble when you are building your own custom Libraries.

I should mention, depending on your DAW, you can perform these Librarian type functions inside the DAW or when running the program standalone. For example, as a VST3 plugin in Cubase, you have access to all the MONTAGE data through its MEDIA BAY function. This allows for convenient cataloging, ranking, etc., etc. When you’re doing sound design in a work for hire situation (jingle work) this cataloging feature comes in handy… you can leave notes and markers to alert you as to what sounds you may already have submitted and to which clients, etc. You can dream up ways to catalog your data… it’s like having your own customizable Category Search function.