When you finish recording, Casio MZ-X500 will save your MIDI recordings as ZMF. What it means is that you can not use your recordings on another brand of keyboards such as Korg .. etc. that accepts Midi file format 0. Meanwhile in the user manual page 61 Casio says that :
■ Types of Data
MIDI recorder is stored on a USB flash drive as-is
or stored as a MIDI file (SMF format 0).
This is not true. It stores as ZMF.
Any help greatly appreciated.