Inno Setup: Dynamically add a component for all files in a folder and its subfolders

Inno Setup: Dynamically add all files in a folder and add a component tag, so during running of the setup the user can select custom setup and select which files to copy.

I'd like to create a Inno Setup file that will grab files in a folder that users can put in there, without having to modify the Inno Setup file each time a new file is added. At the same time, I need the user of the setup file to be able to select which files to copy.

If I do something like this:

Source: "D:\SomeDirectory\*"; DestDir: "{app}"; \
   Flags: ignoreversion recursesubdirs createallsubdirs; Components: dlls

The custom setup only shows the option to copy or not to copy the entire folder.