Sequential circuits samplers

Hi,
seems that I got a 1MB version when I thought I had bought a 512MB.
I read about the PRESET/EXECUTE step that would light a tiny dot at the rightmost lower corner in the display. It did on my P2k. Testing revealed that I could load a disk into the 'Dotted' area, whereas the factory presets would be accessible with no dot lit.
ROM Rev. 4.2. 

Is there a MIDI implementation chart/manual extension available for ROM 4.2 that would sched some light on how to manage the additional space of 512k I just found in my P2k? 

Thanks
Burt