Exclude extracted screenshots from FTS in MS HTML help (CHM files)

We show thumbnails in the help and allow users to click the image to view the larger graphic. It works well, except that the extracted files show up in Search results with non-user-friendly titles (e.g., ag551822.htm, ag550038.htm, etc.). Screenshot attached. I tried inserting Search markers to prevent the extracted files from being included in the Search, but it did not work (I suspect the Search markers only work for splits, not extracts). Then I tried changing the Title variable for the extract to the current title, but that didn't work either (I suspect I'm not using the right parameters in the ini file).

Does anyone know how to 1) prevent extracted files from being included in MS HTML help (CHM files) or 2) set a user-friendly title for extracted files that will show up in Search results in MS HTML help (CHM files)?

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sample-help-showing-extracted-graphics-in-search-results.png130.01 KB