Hi, Bram de Jong.
I’m not 100% clear what you’re asking, but our plugin suite doesn’t have any membership capabilities, such as restricting the calendar view to specific users. Some third-party membership plugins may be able to accomplish this for you.
Our Event Tickets plugin is what enables free RSVPs for events. It is not integrated with registered WordPress Users.
If you want to sell tickets, you’ll need our Event Tickets Plus (ET+) add-on.
Last but not least, we have a pretty great Refund Policy so you can buy one or many of our add-ons and thoroughly test them.
I hope this info helps. Let me know if you have any follow-up questions.