Good evening Charly and welcome to the Events Calendar Support forum!
Thank you for reaching out to us. We are sorry to hear about the loss of functionality with SSL that you have been experiencing.
We will gladly try to assist you on this topic.
I’m wondering if this is not simply a conflict.
As a first troubleshooting step, could you please go through our testing for conflicts procedure (preferably in a staging/dev environment or local install of your WordPress website) and let us know what you find out ?
As an alternative, setting your whole website to https (even when not logged in) might prove to be helpful.
Have a great day!
Geoff B.