Differences between free and pro, esp. Firestore

Hi!
I am thinking of buying the pro-version and tried the free version for now, which I could not get to run. Especially the shortcodes [firestore_col collection_name='Users' display_fields='adr_ort'] or [firestore collection_name='Objekte' document_name='xxx' display_fields='adr_ort'] don’t resolve.

Now I found the line

“*This plugin only supports Real Time Database at the momment. I will add Firestore in the future.”

in the settings.

I am confused…can I use this plugin for Firestore only in the Pro-version; or is another error that I need to resolve the reason for this problem?

Thanks a lot!