Another temp workaround for the background image on your home screen, is to select the picture that you want as your background, then send it to yourself (your phone number) via MMS. When the picture returns, open the message, select menu, contents view, choose open, select menu again, and "Use As Home Screen". At this point you can select the Display Area, and the Transparency (I usually choose 20% - 30%) then click finish.
You can do this for any photo, however make sure that you delete the message from your sent items and inbox afterwards to avoid additional memory usage.
I think the issues with ringtones and wallpapers has to do with permissions on the device, so I hope that sprint collaborates with HTC and gets this resolved soon (I have 5 snap phones)
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