Changes

<!-- windows 8 -->

<check type="registry" condition="equals" path="HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\CurrentVersion" value="6.2" />

</source>

This apporach can be used to limit a package to certain versions of windows; for example Windows7 already has Internet Explorer 8 installed, so to use a package in a mixed environment with xp and windows7 you could write a check like this: