As you can see on my test website:
https://somoscd.es/testsite/memberads/tag
the tags work perfectly.
No registration required to view the ads.
You can check the functionalities of creating, editing, deleting and seeing how the ads are displayed by logging in as a paid user with these credentials:
usr: TestUserPremium
pwd: TestUser
and as a free user with these others:
usr: TestUser
pwd: TestUser
You can also change the graphic theme at the top of the page to see how they are displayed with different themes
As I have commented by private message, there is a variable that indicates whether an ad should be highlighted or not, and it is very easy to edit HTML and CSS to adapt the presentation to your tastes and needs.
The difference in the presentation of ads of one type and another that the plugin provides is basic, it is limited to showing the ads a little larger the featured ads in the Desktop version, but altering things such as the background color, the frame, type and font size and the data shown is very simple.
Also, I have offered to do it for free for you, but if
1) I don't know what the URL of your website is
2) I don't have access
You will understand that I can do nothing more than offer you to reproduce these problems on my test site.