When you configure the user reviews integration and decide on using public ratings so that visitors can say what they think about the reviews, the rating blocks for the public rating method used (Thumsb, Liks or Emotes) will use default settings as defined in the main GD Rating System Pro settings page. But, if you want different rating method settings for user reviews integration, you need to use Rules panel.
Add new rule
Open the Rules panel under Rating System menu, and you will get the options to add new rules, and see the existing rules. Since the user reviews public ratings are given to the reviews and not the post the reviews belong too, you need to set Item Type to User Reviews (find it under Comments -> User Reviews), and for the rating method in the Object Type select Thumbs Rating if you use that for the public rating for the enabled user reviews (find it under Methods -> Thumbs Rating).
Click Override Settings, and the plugin will create a new rule and all the settings for it will be copied from the default WordPress settings for the selected method. And, you will get the new screen where all these settings will be displayed.
Configure the rule
The rule settings page is the exact copy of the main/global settings page for that rating method. The only difference is a single new option on top of the page controlling the activity of the rule. If that option is enabled, the rule is used, if it is disabled, the rule is not used.
But, since there is limited space for the public rating block in the review template, User Reviews addon adds a special template, and it is recommended to use small thumbs size. Here is the rule settings for thumbs styling recommended for this integration: