Always check your Start Layouts with an xml validator! (I use the World Wide Web Consortium’s) I speak from experience here as a quotation mark ” wasted about 2 hours of my time.

You’re not closing the Tile for the Command Prompt.

<start:DesktopApplicationTile Size="2x2" Column="0" Row="0" DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\System Tools\Command Prompt.lnk

<start:DesktopApplicationTile Size="2x2" Column="0" Row="0" DesktopApplicationLinkPath="%APPDATA%\Microsoft\Windows\Start Menu\Programs\System Tools\Command Prompt.lnk" />