I'm not familiar with the XP sequencer but, barring a Sys Ex dump, all you should have to do is make sure each tracks midi transmit is enabled, set the Performer clock to external and enable the record, then hit play on the XP. There is a chance that you will have to solo each track, which means you may have to insert a note-on event on the first click of tracks that come in later or use the punch in. Depending on whether a patch change is recorded into the XP track, you may also have to define each track before dumping.