Event manifests are unversioned. Modifying them after install leaves the modified date > creation date. Util:EventManifest will modify after install because it uses XmlFile to modify the manifest to point to an installed path of a resource file.
To fix this I suggest adding an attribute to XmlFile that says to either reset the modified date to the creation date, or preserve the modified date across edits. Have EventManifest use this attribute.
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