Hi there, @Hamilton. Welcome to the Community!
Hope you don’t mind but we moved your question out into a new topic as that error wasn’t mentioned in the other thread so it’s likely a different issue that you’re running into when attempting to create the Zap.
Can you try closing any zapier.com tabs in your web browser, then open a new browsing window/tab and try going back to the Zap or try creating a brand new one to see if the issue persists? And I’d also suggest clearing your web browser's cache and/or opening the Zap in a private browsing window to see if that helps to resolve it.
Keen to ensure this gets sorted so please keep us updated on how you get on with this. 
Hey @Hamilton
Just wanted to check in to see if you got everything working? Let us know if you need any further help!