To be able to configure and use the block, you first need to setup SAML for your Softr app. You can learn what SAML is and how to configure it on Softr here.
Please, note that the feature is available only for Business plan customers.
Here, you can customize the Logo, Title, and Background Image of the signin block. Moreover, it's possible to set the login button text and choose what page the user should be taken after logging in.