Hi Michael Champenois,
The reason you are getting this error because there could be a slight error in your show home microflow. The best way to tackle the problem is add a breakpoint in that microflow’s first activity and check the value in variables tab.
I think after the anonymous user completes the sign up you can call a microflow on sign up button where you apply logic to register the user and at the end you can use show page activity to redirect it to desired page.
I am attaching a screenshot for your reference. Here I have checked for a value and redirected to that page.
Hope it helps and let me know if you have any questions around that.
All the best!!
It turns out that SAML created a new version that fixed the problem.
I also went ahead and followed these instructions for deleting old jar dependencies. These instructions exist on the release notes for about half of the SAML releases, but not for the new release that fixed the login problem. However, I went ahead and deleted the old jar dependencies by navingating to the userlib folder in file explorer, searching ‘SAML’, and deleting the results.