Hey Tim,
Thanks for reaching out to us!
I’m sorry to hear that you’re having trouble with The Events Calendar working with your menu. I took a look at your site and I can see that there definitely is something funny going on with the menu.
I inspected the menu element and it appears that the “News” menu item is being highlighted because of it being seen as a parent page of the calendar.
As a first test, is there a page on your site called “Calendar” that is a child of the News page? If so, try removing or renaming that page (renaming the slug as well). You could also check how the “Calendar” menu item is being added to the menu under the “Appearance” -> “Menus” section in your dashboard. If it is being added as a custom link it should be receiving the proper classes and highlighting like normal.
Finally, you could test the current configuration with a default theme (following the testing for conflicts instructions here) to see if the highlighting goes back to normal on the default theme. This will help us determine if it is a conflict with your current theme.
I’m sorry I wasn’t able to give a direct answer but hopefully after testing these few things we can get this issue sorted out for you.
Thanks!