Hi Sascha! Thanks for checking out The Events Calendar–I really hope it’s a good fit for your project. 🙂
The Events Calendar and PRO do not specifically support a Register button. However, we do offer ticketing add-ons that allow you sell and reserve tickets for an event. We also have an add-on that integrate with Eventbrite, which another good route for taking registrations. In fact, you can check out a demo of the Eventbrite Tickets add-on here.
Will any of those options work for you? Feel free to let me know if you have any follow-up questions here and I’d be happy to help.
Cheers!
Geoff