I’m consistently having this behavior occur.
Start Scrivener, and the Template Wizard appears. Select a project from the “Open Recent” list, and open the project. There is a pause (up to 30 seconds) whilst Scrivener assembles the project items for editing.
At this point, the project open and I can work with it BUT Template Wizard does not close. I have to go back and click “Cancel” to close it out.
I’ve also had this a couple times on the “Open Existing Project” option, too.