Try the Roland PNC 1000 or the 1000a driver, if it doesnt have its own driver, infact you may also try the refine drivers in there as well.
Does the machine cut a sample test cut, (a square within a square) this should be a simple button push button from the display on the cutter. the next thing to try is after we have assertained that the software is ok and the machine is ok is the connection, in between, is the cable ok, is it "known to be working".
Also what are you trying to cut? is it something you have created within signgo or is it a picture you have pulled in? I would initially try to cut your name or something, type it into the program (signgo) directly and try to cut it that way. its a while since I looked at signgo so I cant give you step by steps with it.
After you eliminate or run through some of these things please come back and give us some more info.
Good luck