You're probably doing something wrong. Either in selecting the Performance from the Library to begin with or in your interpretation of the results. It's unlikely that the system is mis-reporting where the Performance is indexed.

What's your firmware version? It has to be new because MSB=64 is only for the newer firmware (older firmware did not use 64 at all - only 63).

I don't know what I did (bad memory?), but I just checked again and it's MSB 64, LSB 32 😮

32 is for your user area. This is a user copy of a Performance if you do happen to have the same Performance inside a Library. When you press [CATEGORY SEARCH], press the "Bank" section and select NOT User, NOT Preset, NOT All, but any of the other options which would be libraries. You'll see if you pick any Performance that the LSB will agree with one of the library ranges previously outlined.

32 is for your user area. This is a user copy of a Performance if you do happen to have the same Performance inside a Library. When you press [CATEGORY SEARCH], press the "Bank" section and select NOT User, NOT Preset, NOT All, but any of the other options which would be libraries. You'll see if you pick any Performance that the LSB will agree with one of the library ranges previously outlined.

Aww, that makes sense. The Performance I checked through was a [Store]'d copy from the FM-X based library, so it was in the User area. I'll check a Performance directly from that Library and see what the LSB is...

After checking a Performance directly from the FM-X based Library, the MSB=64 & LSB=40
So everything is set as expected! 😉