Auto launch and close IE7 during unattended install?

[NOTS3W]

Is there a way to launch and close IE7 during an unattended install?

I'm using nLite and adding a number of additional registry tweaks through cmdlines.txt. I'm finding that setting Google as a search engine and making it default doesn't work:

Windows Registry Editor Version 5.00

;Add Google as a Search Engine
[HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\SearchScopes\Google]
"DisplayName"="Google"
"URL"="http://www.google.com/search?q={searchTerms}&rls=com.microsoft:{language}&ie={inputEncoding}&oe={outputEncoding}&startIndex={startIndex?}&startPage={startPage}"

;Make Google the default Search Engine
[HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\SearchScopes]
"DefaultScope"="Google"

I've checked the registry and those tweaks are in place before I first run IE. When I launch IE, it only lists Live Search and the registry entries are replaced with new entries that refer to a GUID:

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\SearchScopes]
"DefaultScope"="{0633EE93-D776-472f-A0FF-E1416B8B2E3A}"
"Version"=dword:00000001

[HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\SearchScopes\{0633EE93-D776-472f-A0FF-E1416B8B2E3A}]
@="Live Search"
"DisplayName"="@ieframe.dll,-12512"
"URL"="http://search.live.com/results.aspx?q={searchTerms}&src={referrer:source?}"

If I do the same Google tweaks after closing IE, they work fine. The next time I open IE, the default search engine is Google.

Oddly, other IE tweaks from cmdlines.txt (like closing unused Favorites folders and suppressing the Welcome to Tabbed Browsing page) work as expected before and after the first run of IE.

I'm not sure where or how to launch and close IE. Does anyone know how to do that? Then I'll have to learn how to add those tweaks to GUIRunOnce so they happen afterwards.

If I add those keys to HKLM or HKU, will that help?

FWIW, although I don't think it matters, I'm testing the installation in Virtual PC 2007 using Windows XP Home Edition.

Thanks for your help.

Ray