Hey Spud!
Sorry to hear about these problems. I took a look at your site for quite a bit and was not able to produce a JavaScript error in the checkout process, although I did encounter the issue you described where the “Loading” circle just hangs there, spinning.
I’m really sorry to have to recommend this so early on in the thread, but: it appears like the best test to do here is to run through or set of troubleshooting steps which are outlined here → https://theeventscalendar.com/knowledgebase/testing-for-conflicts/
Those steps may seem tedious, but they’re genuinely much quicker to work through than it seems. If you do those steps and check on the checkout process after each step, you’ll get really valuable information from doing so.
Let us know what you find here! Is the behavior affected anywhere along the way? Do things work fine in a default theme or anything like that?
Thanks Spud,
George