To make sure that a file is not removed during uninstall you can mark its component as Permanent.
You can use a New Text File Update operation in "Files and Folders" page. First you should recreate the folder structure under "Windows Volume -> Windows -> System" folder. After that you can add the update operation in the "etc" folder.Instead of replacing the file, is there a way to make sure my lines are added?
Regards,
Cosmin