Colors and fonts not saving. Cannot customize

I installed and tried this plugin. Uninstalled it after a couple of hours and came back to it to try again. I cannot get the right or left colors and font settings to work.

The plugin saves my settings but it doesn’t make a difference when viewing the menu on the website. I’m sure it is a conflict with CSS and my theme somewhere but I cannot find it. And, I cannot purchase a plugin that is not working on my site or my theme. The developer’s website offers no help with this issue.

And, before you say this is my problem or my theme’s problem, this plugin is 1% of my site. My site doesn’t revolve around you or this plugin. You should be able to offer some form of advice or assistance.