Using an External Sequencer (ie Pc) with Roland G70

I own the Roland G70 Workstation Keyboard and I`m very happy and impressed with what it can do, However as good as the onboard Sequencer is on this keyboard, I`d still rather use my external sequencer on my computer. Is it possible to do this using all 16 channels on this keyboard (For normal recording-NOT USING THE ARRANGER) and if not, Has anyone any idea if roland in the near future is looking at implementing this idea of using the G70 with external sequencers.(ie-Implementing this in another software version for the G70) At the moment I can only access the Upp1,Upp2,Upp3,Low1,Low2,Bass for external sequencing.Only 6 channels, I`m using the other ten channels from another keyboard as a result.
I`ve already posted this question to Roland but as yet still havew`nt heard back from them.So if anyone out there has any idea out there I`d be very grateful.
I`d really appreciate advice if you can give it as I`m completely stumped.

I know that the G70 is mainly an arranger Keyboard but I was just so drawn to it that I had to have it, The Sounds are Perfect.