Install OS into Kurzweil using iMac? Options

Kurzweil has come out with version 2 of the OS for its PC2 Performance Controller released about a year ago.  But I just can't seem to install it.  Kurzweil's instructions say to first upgrade the bootblock, then install the system.  The only sequencers they recommend for Mac users are MIDIGraphy 1.4.3 and Alesis Freeloader (very simple and user-friendly).  I purchased the cheapest USB interface I could find--Roland UM-1--and installed the accompanying software (USB MIDI Driver and OMS).  My iMac is OS 9.1, which definitely sees the interface. But opening the Kurzweil file with either sequencer and launching it produces nothing.  I'm wondering if the problem might be with the interface, the OMS program (should I use MIDIfree, included with the Roland software?) or the iMac.  Kurzweil offers no further guidance other than to warn against certain sequencers like Windows Mediaplayer.  I notice that the PC2 is too new to be listed in the Roland, OMS, or MIDIfree materials.

Any ideas appreciated.

Sam

[cc]

I am working with Samuel at trying to load the Kurzweil PC2 Version 2 operating system.

Using the Roland UM-1 Mac-to-keyboard USB interface cable, we have established MIDI contact from both an iMac and a G4 using MidiGraphy--it plays songs just fine.

I don't know if MidiGraphy is transferring sysex commands, and don't know how to know. Can anyone help us with that?

When we try to 'play' (i.e. download) the operating system (which exists as a MIDI file), the keyboard recognizes it and the transfer begins just fine. Then it hangs--sometimes about the 5th or 6th 'measure,' and sometimes about the 17th (out of 27).

Any ideas?

Thank you!