Hi hooperman13,
Thank you for your time to write a review! It will help improve the plugin.
I am sorry to hear that the plugin did not provide the desired result.
The plugin is a toolkit for optimization, it is not a plugin that ‘delivers’ a result. It is always required to configure the plugin correctly before a result can be measured.
The plugin should, however, install without options that could impact the look of a website. For example, CSS delivery optimization is disabled by default.
Did you enable any features after plugin installation? And did you configure Critical CSS?
The problem you describe appears to be related to the quality of Critical CSS.
Did you try the Critical CSS Quality Test and is the correct view displayed in the right-side view?
The example below shows a font problem caused by invalid Critical CSS (the search icon in the left-side view).

Creating Critical CSS is a difficult and meticulous task. More information about the essence of Critical Path CSS creation can be found in the following blog (with video) by two Google engineers.
https://addyosmani.com/blog/detecting-critical-above-the-fold-css-with-paul-kinlan-video/
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