Coursepress Pro Cannot Purchase Course with Marketpress After Upgrade to v2

So I have upgraded our existing course to v2 of Coursepress 2 and the course does appear to have been copied through correctly to the new schema.

HOWEVER, when we go to hit the 'Add to Cart' button there is a spinning wheel that comes up briefly and then nothing.

There is no pop up screen for payment details etc.

Course URL is

This is a real problem because no one can register for the course since 'upgrading'