When running Layout, beneath File, there should be a link called “Create Hyperlynx Files”. If this link is missing, edit the file ~/mgc/startup/layout.startup (or create the file if it doesn’t exist) and add to it:
$insert_menu_item($menu_text_item("Create_Hyperlynx Files",
"create_hyperlynx_files()"),,"file_pulldown",@last);