When you save a single sequence on the MPC 2000 it saves it as a MIDI file. Unfortunately this puts the sequence into a standard format that depending on what you have actually sequence will cause in correct play do to misassigned parameters.
To avoid this save your sequences as "MIDI FILE TYPE 1" this retains the format of the data. If you save your sequence as "MIDI FILE TYPE 0" it runs all the data together.
The selection choice comes up during the save sequence function.