You did not understand a little.
Can this widget "Most Voted Reviews" display popular posts one category, and not all categories of the site?
From the screenshots, I see that he displays posts from all categories and I am not sure if he can deduce from one particular?
I have 5 categories on my site
There is a category Music
There is a widget where there should be only posts from this category.
It is necessary that the posts were not by date, but by the most appreciated.
Is it possible in your widgets?