First, you must press [STORE] to store your Performance to the User Performance Bank.
“Store“ is the act of writing the changes to the MOXF’s internal memory.

“Save“ is the act of writing the MOXF data to a USB stick for long term storage.

Only the “Stored“ data gets “Saved”.

You do not Save a single Performance. Performance data is a set of “pointers” — they point to Voices that are already in memory. A Performance is made up of as many as four Voices, that are either Preset or User Voices.

Say you have a Performances made up of Preset 1, Voice 001 “Full Concert Grand” in Part 1. And an edited User Voice you made that is stored in User 2, Voice 128 named “Becka’s Pad”. The Performance memorizes the locations of the Voices, not the actual data — it *points to* the locations. In addition you can apply *offsets* — for example, you might raise or lower the octave of one or both of the Parts (the Performance allows you offset parameters with destructively changing the original Voice. This way “Full Concert Grand” and “Becka’s Pad” can be used in other Performances tuned differently, or setup as a Split.

If you were to replace User 2, Voice 128, (By loading in a different set of User Voices) the Voice now in that location would serendipitously replace your original in the Performance.

This is why Performances are Saved as apart of the “All” data File Type... In order to ensure that your creation, “Becka’s Pad”, is returned to User 2, Voice 128, you must SAVE Performances in an ALL data file (.X6A). You can, however, load a single “Performance” from within an ALL data file, but it will warn you that your data contains User Voices... which is the firmware asking you to verify that the proper Voice is loaded to that User location.

If you load the single Performance and discover your creation (Becka’s Pad) is NOT there in that location (User 2 Voice 128), you must go back to that .X6A ALL file and set the Load Type to “Voice”, then Load the single Voice User 2, Number 128, “Becka’s Pad” back to where the Performance data expects to find it. You see, the ALL data file contains all the data, the User Voices, the User Performances, the Songs, the Patterns... you can load a single type from within the All data file by setting the File Type = single xxx