Hi and welcome back,
Sorry to see you’re having a bit of struggles with the transition. If you create a new ticketed event and go through the process, does this same behavior occur or do things act as they should?
When transitioning content from A to B, often times it’s a matter of the order you import things. An example would be our own plugins. In order for locations and organizers to attach to the correct event, we recommend importing locations and organizers before events, that way the organizer and venue information “exists” and the imported events can properly refer to them in the database based on it’s relative data. More info on the matter can be found here: https://theeventscalendar.com/knowledgebase/using-the-events-calendars-csv-importer/
Obviously, there’s the potential a bug is present in our code, but if you could provide the results from adding a fresh event and possibly reexamine your transition approach just to make sure things were done in the proper order, it will give me a much better idea on how to proceed.
Thanks and have a great evening!