No problem. The main complaint I get is that it’s unclear exactly what you’re supposed to do with the plugin. The problem is there’s no one way to use it correctly.
I suggest, if you’re not entirely sure what you’re doing, to choose production mode, yes on compress css, use closure as the minifier, and do not force the scripts into the footer. You’re least likely to break things this way.
Then, in the javascript and css tabs, select all of the files. The plugin doesn’t actually do anything though until you request a page. So, after saving those settings, you should visit the main page of your site. The first request may take longer than usual to complete. That’s because the plugin is finding the files and compressing what is needed. After that though it should be faster.
In some cases one or two js files may cause errors when being compressed. That is why I allow you to uncheck certain scripts. Should any script cause an error you can remove it from the list and clear the cache. I hope that helps?