Joseph,
I was recently able to get some zipped SY77 files via e-mail, unzip them, copy them to an SY-formatted double-sided double-density disk, and then load them into my SY77. I changed some of the file extensions so that each file on the disk had a different extension, i.e. bank1.T01, bank2.T02, bank3.T03, etc. All of this worked flawlessly on my Mac, so you should have no trouble on a PC. Good luck!