Risks: None i know of unless you corrupt your file.
Tools: Xtaf Xplorer:http://www.mediafire.com/?taz3ewlzmcm
Modio- [ Register or Signin to view external links. ]

Tutorial
Step 1:
First move one of your themes from hard drive to usb.

Step 2:
Now open xtafxplorer and find the file that starts with 000 now open to next folder.

Step 3:
Shrink xtafxplorer and open modio.

Step 4:
Once in modio choose other tools and theme creator.

Step 5:
Add the pics you want and save to desktop.

Step 6:
Reopen xtafxplorer and inject the file into the folder after the three 0's

Step 7:
Move back to xbox and choose your new theme and enjoy.
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