Hi,
Thanks for the interest in the Events Calendar and the AddOn for WooTickets.
It is hard to tell if there will be an issue with your theme.
We work to make our plugin use the WordPress provided methods, but it is not always the case that everything works correctly.
You can try to use the free version of our plugin from WordPress.org and see if it works on your site and if does then the Add On should work, but I cannot say for certain.
The Events Calendar
Thanks!