Hi Alex,
Community Events will add a front-end form that will allow users to create events from the front end of the site, even with a subscriber account.
Regarding the notice at the top of the page, this is not something that comes with The Events Calendar, so it may be coming from your theme or another plugin. We are not able to provide technical support here in the Pre-Sales forum, but you can post this issue in our community forum on wordpress.org, which we review weekly to check for bug reports. If you need more in-depth support, you will need to purchase a license.
Our knowledgebase is a great place to start looking for answers. You can also search our premium forums to see if another user has posted about a similar issue. Testing for a conflict is the best place to start your troubleshooting.
Thanks,
Jennifer