Can anyone recommend a USB-Serial cable to use on a Mac running Windows? My Keyspan USA-19 works perfectly running under the OS X and on Windows machines. But, when I try downloading firmware from our mac pro running Windows to a board my son and I are messing with, I get validation errors. (For various reasons I don't fully understand, I need to be doing this download from Windows. I have tried doing it from OS X and no go). Thanks!