My grease pencil layers are in object mode, I've restore factory setting before to add the cult tools addons, I've try with the original addons and modified addons.
Sometimes it work, it work often if i'm in perspective mode. I really don't understand I search since 2h.
I'm sorry, Martin. That's very annoying. Unfortunately the addon used in this exercise hasn't been maintain for years and it's reaching obsolescence.
I recently did a livestream about a newer addon that can replace the functionality of Grease Cut.