Grou Random Image Widget: Where are the options/how do I add an image folder?

Hi all, I just installed Grou on my blog https://coffeeandirony.org/ and it’s not showing up in my Settings or anywhere in my dashboard. It does show up under my “installed plugins” but I can’t get to options from there, it just takes me straight to the php editor of course. It’s very strange because every single other one of my plugins does show up and I’m able to adjust its options.

I’m also confused about the path for the images – do I need to create a folder in my media library? How would I do that?

https://www.ads-software.com/extend/plugins/grou-random-image-widget/