Hi Kathleen. Thanks for the note. To start, regarding that warning message: you can ignore it. It’s wrong, and is something we’ve got on the radar to strip out for the next release – come 2.0.8 it will not be an issue anymore. In the interim, so long as you’re running 2.0.7 for both The Events Calendar and Events Calendar PRO, you’ll be fine.
Regarding the WP Router Placeholder page. Have you updated to 1.0.1.1, or are you still running 1.0.1? The 1.0.1.1 release – which just came out earlier this week – seems to have patched the issue for most (but not all) of the users we’ve heard from so far. I see you’ve posted this over in the other thread (https://theeventscalendar.com/support/forums/topic/wp-router-placeholder-page/page/2/) so I’m going to continue responding over there and close this one down…but if you can confirm there that you have updated to the new build we can proceed appropriately.
Thanks for your support and patience so far.