Picture wall desklet

[Jopp-Lm]

I checked the core plugin "digital picture frame" desklet shipped with Mint because I wasn't happy with only one instance of this otherwise nice plugin ! (my pics cycle every 15 minutes or so, therefore I've no issues)

I made a copy of "digital picture frame" and found out, all I had to do was to add a single string to "metadata.json" to get more instances, nice!

Well, the story doesn't end here, otherwise this post would be superfluous.
Also, I found out that "digital picture frame" covers my directories on the desktop.

So my question is:

How to push displayed contents of the "digital picture frame" desklet behind the desktop icons?

Unfortunately i don't have experience with javascript in particular, only css and bash.