If your tones don't sync properly to your iOS device, uncheck the option "Sync ringtones" from the ringtones tab when the device is connected, sync the device, check the option and sync again.
If it still not works select the file in question and click CTRL-I to Get Info. Does the filename end in .m4a or .m4r?
Close the Get Info. window, right-click on the file and click Show in Windows Explorer. If it's m4a you need to change the extension to .m4r, then drag the file into iTunes.
If it doesn't work, please contact with Apple (as it's an iTunes download), but I already tell you that they're going to say that the problem is that you haven't updated, so tell them that you have iOS 8.