Hi Pete, and welcome to the forums! Sorry you’re hitting some trouble here with the WooTickets snippet, but hopefully we can figure it out here together. 🙂
Yeah, I see what you mean. I was able to recreate the issue when I reverted to an older version of The Events Calendar and tried to update with the snippet in my functions.php file. No bueno!
This certainly wouldn’t be an issue in all situations, but for where does come up, it seems to be related to checking whether the TribeWooTickets class is set before running the snippet.
Try wrapping each block of the snippet in a conditional that checks for the class first. For example, here’s what that looks like for the snippet to move the ticket form above the event description:
https://gist.github.com/geoffgraham/eb1789cc42291a23eb36
Give that a shot and let me me know if it helps.
Cheers!
Geoff