Alright I've looked the skill tree over several times for spelling errors and typos including extra spaces. I found nothing. I did notice I structured this skill tree differently. I did all of lane 1, then all of lane 2, followed by all of lane 3. Then I made the end of lane 1, 2 and 3 parent nodes to a node at the end of lane 2. Lane 1 and 3 are each 6 deep and lane 2 is 7 deep. Would that cause the error? Is the parent node at the end of lane 1 to far away from the final node in lane 2? Let me know what you think. I would hate to have to restructure this skill tree all over but I will if it can't be helped. Thanks again.
Viewing post in Alchemy Skill Tree that uses Common Events?
That shouldn't lead to an error. If you're willing to upload the Techtree.json to https://pastebin.com/ and share the link here I can check the tree for you.
Best regards,
Felski