What is free for the free version and useful to download?

There is a page with extensions from where you can download them after entering your login and password
www.modeliosoft.com/en/downloads/msoft-m...r-modelio-4-1-x.html
What can actually be fully used with the free version, in terms of the fact that in the extension store some of these modules are marked as commercial?

I read that the modules have a trial period of 10 days. Are the different modules the same price or are they sold at different prices?