Larian Studios Forums Divinity: Original Sin 2 - The Modding Dungeon Divinity - Original Sin 2 - Modding Troubleshooting Dialog Flags don't seem to be working for me?

Have you built story at least once already for your mod? Both the quest update and starting trade through setting a flag are handled by story scripting from the Shared mod, and story scripting only becomes active once you built story for your mod (= compiled the story scripts, which includes the scripts from mods your mod depends on, such as the Shared mod).