Customizing Testimonial Rotator

I can see where at least two people have asked questions, with no response. Is it as basic as, “You can’t” ? Please advise.

This set of plugins looks promising, but there’s a lot of mystery in configuring it.

I set up a few testimonials and they load on my page, but I can’t find where to set the duration (very important), or how to style them like any of the examples (dark background speech bubble etc.).

I’d also like to see arrows for navigation and dots below as some indication to the user that there are more than one testimonial. This is pretty obvious UI/UX.

Someone suggested editing the php files, but this is not a great idea as the edit will disappear when the plugin is next updated.

Is it possible to make these customizations? How?