You can specify most of the install operations regarding files, folder or shortcuts in the Files and Folders page.
Add, Remove files to the installation and set the file properties.
Add and Remove folders to the installation.
For "Project Templates" and "Item Templates" category, the resources needs to be placed under the Extensions Folder in new folders, ProjectTemplates and ItemTemplates.
The right pane lists all the files and their details from the selected folder of the left panel. If a file doesn't exist anymore at the specified location, it will be shown with a question mark icon and “???” as its size. You can restore this file by double-clicking it and setting its correct path.
Working with files in the Files and Folders page on the Visual Studio Extension Project.
Working with folders in the Files and Folders page on the Visual Studio Extension Project.