Thanks for sharing, Johan.
It's think it's a common mistake for people with little marketing experience to overestimate conversion rates (from launch notifications and social media ads). So very helpful that you share your data.
You were very clear in the campaign with the goal being to create a physical book and not about whether the game would exist and with how many bells and whistles. I liked the integrity of doing it this way though it may have cost you a few FOMO junkies.
Great job to fund and deliver within one year.