Good news. I was reading some of the other forums and decided that I had the exact same problem as other people. It stopped the cut short or cut a line to home position.
I went out and got a Keyspan USB to Serial adapter (Which Keyspan has no stock of right now). I could believe it, it works perfect. made about 15 cuts today and i love it.
The only other bit of information i can add is when your in the cutter settings if i pick refine selltopia than all my images are about 25 to 30% larger than the measurement
says it is, and as it were i did buy my cutter on Ebay through selltopia. But If I pick refine MH721 the cutter works perfect.also i found that using the keyspan adapter that as long
as the baud rates are the same on signcut and the cutter that i could use 4800 or 9600 it didnt matter. hope this helps people out somewhat.
(P.S. I'm running an MacBook Pro 2.33GHz Intel Core 2 Duo, Mac OS X version 10.4.9 , and a US Cutter Refine MH721 bought from Selltopia.)