I've put in a support case, but am wondering if there are others having trouble with the Pardot Lightning app? I have several users who can't get it to load - it spins and spins and then will often display an error "the page has an error, you might just need to refresh it". I'm concerned that with the switch over to Salesforce SSO they will lose access to Pardot next week. I've read and re-read all the instructions about setting up and providing access to the Lightning app and so far nothing has worked.