I always deploy images in attend mode, using an unattend file with the image built in WAIK. Within the unattend there is a place to set location and language, as it would with an regular install. So from my experience it doesn't matter what the image is listed as on the image selection.
For example I use:
For Timezone:
<component name="Microsoft-Windows-Shell-Setup" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<TimeZone>E. Australia Standard Time</TimeZone>
</component>
</settings>
You can find all the various timezone formats here: http://technet.microsoft.com/en-us/library/cc749073%28WS.10%29.aspx
For locale and language:
<settings pass="oobeSystem">
<component name="Microsoft-Windows-International-Core" processorArchitecture="x86" publicKeyToken="31bf3856ad364e35" language="neutral" versionScope="nonSxS" xmlns:wcm="http://schemas.microsoft.com/WMIConfig/2002/State" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<InputLocale>en-au</InputLocale>
<SystemLocale>en-au</SystemLocale>
<UILanguage>en-au</UILanguage>
<UILanguageFallback></UILanguageFallback>
<UserLocale>en-au</UserLocale>
</component>