For a discussion of the Mega Steel guitar please see the following article:

MONTAGifying Motif XF Performance: Free Fall

This tutorial explains how the “Mega Steel” (Part 3) is constructed.
Since you have a MODX the 512 Motif XF Performances can be downloaded (free) from the Official Yamaha MODX Download Page

The article was actually written for the MONTAGE, so, while everything discussed applies to your MODX, the navigation steps must be adjusted to fit the MODX interface...
... you must use the [PART SELECT_MUTE/SOLO] button and screen options to navigate the architecture.

Let us know.

Bad Mister, good tutorial, thanks!

There is only one thing I cannot understand.
Fixed just drums only, this mode hasn't chord logic.
Normal and Org Notes are result the same.
When I record and convert my chord C3-E3-G3 then arpegio play C1-E1-G1 or C2-E2-G2 or ... C5-E5-G5 full keyboard range!
Both Normal and Org Notes.
I hear built in some styles use fixed diapason and play only limited octave to respond to aplicature.

_C named arps it's about it (and not _N named)

How it converted?

Maybe exist secrets? DAW generated MIDI file with secret channel manipulation? 😮

MOTIF: "Free Fall"
chord playing without transpose like Yamaha PSR
like _C named arps
what a secret?

Have Arpegio CASM section? 🙂