Thanks to this forum:

http://www.howardforums.com/showthread.php?t=1456857

I was able to add custom ringtones to a Verizon Samsung Sway.  My approach was a little different and straight forward.

First off, when plugging to USB cable in for the first time (I have a Samsung Omnia i910, so cable works with Sway), Vista tries to install drivers.  I forget which screen but after clicking so many times for online search, the last page lead me to a link that enabled me to download and install this file:

http://mrhop.com/pub/20070813082717640_Samsung_USB_Driver_Installer.exe

So I removed the phone, install, and rebooted as instructed.  Then after reboot, plugged up phone (make sure to keep USB mode on phone to Ask, and don't select anything when prompted on phone).  Vista sees everything and magically a COM8 appeared.

 So I downloaded QPST-2.7 BULD 263 from isohunt cough dot com.  Followed instruction from howardforums.com and things work like a champ.

 To reduce the number of phone reboots from two to one, after the initial reboot and edit of file MrInfo.db, you can copy and paste lines to create new entries for every new mp3 copied to /brew/mod/mr folder.  Then when done, just copy file over and reboot one time.  This way you don't have to reboot to get new MrInfo.db, and edit, and reboot again to apply changes.

Another thing, when USB cable is used, set the phone to ask mode for USB.  And when asked, don't select anything!  Very important, as the drivers will do different things depending on your choice when asked.