As for the IE issue, the only way I got it to consistently display was to create an IE shortcut under %ALLUSERSPROFILE%\Microsoft\Windows\Start Menu\Programs\Accessories since there is no shortcut to IE there by default. If you use the other optional location (%APPDATA%\Microsoft\Windows\Start Menu\Programs\Accessories) I found that I didn’t actually get it when I logged in the first time. Seemed like maybe a timing issue possibly because the Start menu doesn’t exist in time for the Start screen to reference it when a new profile is created.
So I set the IE shortcut line to this and that seemed to work better for me:
<start:DesktopApplicationTile Size="2x2" Column="0" Row="2" DesktopApplicationLinkPath="%ALLUSERSPROFILE%\Microsoft\Windows\Start Menu\Programs\Accessories\Internet Explorer.lnk" />