Running Tropy first time with existing database

I’d like to share a database with someone who has never run Tropy before, and have them open my Database.

It seems that the first time Tropy runs it forces you to create a new database. I don’t see an “open existing” dialog anywhere. Am I missing something?

Yes, the new project wizard is in need of a complete overhaul. You can still open an existing project from there by using the Application Menu on macOS File -> Open or using Cmd + O on the keyboard. On Linux and Windows the window menu is hidden, but you can make it appear by pressing the Alt key or using the Ctrl + O shortcut.