Hi there Simon,
Thanks for taking those screenshots for me.
Would you be able to uncheck to disable the two JavaScript list settings so we can continue to narrow down the scope of the issue?
My current suspicion is that one or both of those settings may be running into some other JavaScript on your site causing the form to display differently than expected.
Let me know when both of those are disabled so I can do some further investigating.
Thanks!
-Kath