Hi Allan,
Welcome to Yamaha Synth!

I include the instruction below... you'll need to use the Editor for the S90 XS and the Editor for the Motif XF; Basically, you will use the S90 XS Editor to create a Motif XF file that the Montage can read directly. Both Editors are available free, download from http://download.yamaha.com

S90XS/S70XS Voice Compatibility:
The voices of Yamaha’s S90 XS and S70 XS synthesizers can be loaded into the MONTAGE by using both MOTIF XF Editor Standalone/VST and S90 XS/S70 XS Editor Standalone/VST software. The steps for loading a voice file are as follows:

_ Save the voice data in the S90 XS or S70 XS. Select either All Files (.X2A) or All Voice Files (.X2V) as the file save format.
_ Copy the saved file via USB flash memory, and open it using S90 XS/S70 XS Editor Standalone/VST.
_ Save the copied file using S90 XS/S70 XS Editor Standalone/VST. Use the file extension .X2E.
_ Import the saved .X2E file using MOTIF XF Editor Standalone/VST.
_ Save the imported file using MOTIF XF Editor Standalone/VST. Use the file extension .X3E.
_ Load the saved .X3E file into the MONTAGE via USB flash drive.

If you get stuck, post back here.

Thank you ! Using the above, I've been able to get my favorite S90XS Voices into a Montage Library file. Still learning though, through trial and error, how to work with files in the Montage.

User and Library Files

Thank you for the link. I've read through it a few times, while sitting in front of the Montage. Understand the differences between User and Library files, and like the concept. Having a set of Library files to access, and one main User file - into which I can import Library items, and continually update the User file - makes sense.

But, here's where I'm hitting a snag: I'm just not picking up on the step-by-step process involved in creating a Library from the .X3E files that were saved onto USB drive (these files appear individually as User files when I open Utility on the Montage). Also can't seem to grasp creating a Library file from my User file. The Bosendorfer piano Performances loaded fine, but that was an already set-up Library (currently the only one in my Montage). So a one-step-at-a-time tutorial covering navigational procedures for the four sections of Utility>Contents would be great. How do I move single Performances / blocks of Performances between the sections ? How to remove / delete any of those ? For some reason I'm not grokking moving around within Utility>Contents. I did watch the sub-titled video from Mossieurs regarding the Utility>Contents area, but had difficulty grasping any step-by-step concepts. It did reinforce your points in the blog post, but the few navigational concepts presented got twisted in translation.

Thanks much for additional insights here, or any other helpful links !

But, here's where I'm hitting a snag: I'm just not picking up on the step-by-step process involved in creating a Library from the .X3E files that were saved onto USB drive

You can LOAD the .X3E file directly to a Library location (temporarily).

Press [UTILITY]
Touch "Contents" > "Load"
Set the CONTENT TYPE = Library File
Find your .X3E listed
Touch its box to install the data to a Lbrary location.

.X3E files will not contain any Waveforms and Samples, just Voices in Motif XF format. The Montage will install 544 Single Part Performances (512 Normal, 32 Drum Kits) to the next available LIBRARY.

Once installed, you can play through them as follows:
From the [PERFORMANCE (Home)] screen
Press [CATEGORY SEARCH]
Set the BANK = your newly installed Library
Set Main to ALL

Listed below will be the 544 installed programs. Using the "Default" list you can step through them right on this screen. Using the Inc, cursor arrows, touch the names, use the PAGE DOWN arrow on the lower right front panel, etc.

If you want to keep choose items from this Library, this is when you use the IMPORT from LIBRARY function. By importing the individual Performances from the Library to the User bank (which has 640 locations) you can start accumulating the ones you will keep permanently. Think of the User area as where you will build your permanent Library.

[UTILITY] > "Contents" > "Data Utility" > touch the "Performance" folder... Here you can view what is in your current USER Performance Bank. The count will show you 0/640 if your User Bank is blank.

"Contents" > "Import Library" > touch the item that represents your temporary Library.
Place a check next to each you wish to import to the User area, or "Select All"

When you've assembled the data in your USER BANK (think of it as your work area) you can now tweak the Performance, add Motion Control functions, new Effects, new combinations, etc., etc. STORE them to the User. When you everything as you like, that's when you SAVE your USER BANK as a LIBRARY FILE to a USB stick.

This becomes the data that will become your permanent Library. (.X7L)
Install the new data Library by loading as a LIBRARY FILE
Delete the temporary Library.