Hi,
after the two last update of the calendar I had to disable the plugin because of 500 error on the whole website. The final solution to the problem was to completely remove the plugin and reinstall it (through the dashboard).
Now the plugin is working fine again, but I'm not able to change the theme or edit any of it's value. It always ends up in a 500 error.
Unfortunately, I'm not able to access the server logs from my hoster.
Any idea what the problem might be or how to solve it?