Hello goliard,
I'm glad you manage to use it well. You should take a look to the last update, it will make your experience better. About your observations :
- You can delete a scene, just select a scene and click on the red button called "delete", next to "duplicate" and "rename".

- It's a good point, i will think about it.
- You can have many character appearance in the last update:

- It's fixed in the last version, i managed to make a test with more than 50 scenes without any bug.
Thanks again for your feedback, it helps a lot !