In authentication requests, SP Entity ID and ACS URL are normalized (made lowercase) by the Gateway / Perspective, but not by the Designer. This is an issue when the authentication service is case sensitive, necessitating manual setting of the SP Entity ID in the IdP and defining multiple ACS URLs (one lowercase, one not) in the authentication service. Please normalize SP Entity ID and ACS URL in Designer authentication requests for consistency with the Gateway / Perspective.

Reference support ticket #177084