I am experiencing a similiar issue, although when I send the artwork from signcut to the plotter it will start cutting (if it starts cutting that is) right in the middle of the project. It will cut the last 1/2 of the job fine, but wont cut the first part at all.
And Billy when you intall signcut on the PC, it will install a plugin to adobe illustrator to be able to send what you worked up into signcut to cut it. Illustrator is very related to plotting in my opinion, since it is a vector art program, which is what the plotter uses to cut from unless this setup is totally different from everything else I have worked with in the past.