Real Media Library displays as a single column of thumbnail with no features

I need some help. I’m rebuilding a client’s old website on the Wordpress platform, and since they old website had a fully featured Gallery function, I was very pleased to read that Real Media Library provided all these same features.

I read the docs, watched the video, worked carefully, created new Page, clicked the new button and got the short code I expected,

[folder-gallery fid=“6” columns=“4” orderby=“rml”]

but when I view the actual website, these 24 images display as a single column of thumbnails with no features! No scrolling, no lightbox!

Here is a link to what I got:

The site is built with WordPress 5.1.1 running [Buildr] theme.

What is wrong?