I did this a long time ago with documents not files.
But it required hard coded document links within the product record. I suppose that data entry could be automated.
For files you should use the public link button:
Should look something like this:
You can remove the description value and it wont show up. Its an optional attribute. Refer information below. the same link you provided has that information.
For each image, use the src attribute to specify the path to the
image. Optionally use header and description attributes to provide a
header and descriptive text that the carousel displays below the