lol... I have connected the Rezound, and dozens of other phones, to many computers, hundreds of times. They are there, where things download too is app specific. The only parts of the file system you can't see are other partitions than the sd storage partitions. You can just make a folder on your sd card called "Ringtones" and put any MP3 or other supported audio file on it and use it as a ringtone, done it lots of times.
I've got that p.o.s. Windows 8.1, which may not matter, and it won't let me make a new folder. She's got so much crap downloaded on her phone anyway, that the phone is probably trying to tell me something. Like "are you serious man? Something else?"