There are some limitations for the Simple Sign component that you need to be aware of:
1. The Template may not be configured with Only Sender Signs enabled
○ In this case, community user will see the error that the there is no signing URL for the current user
2. The Template may not have the Enable Preview and Position Fields option checked
○ In this case, the agreement remains in pre-send state, and no signing URL will be loaded
3. The Template may not have the Enable hosted signature option checked
4. Simple Sign does not support delegation
○ In this case, the other recipient will not be able to access the signing URL
5. Simple Sign does not support Replace Signer (which is a form of delegation)
○ In this case, the new signer will not be able to access the signing URL
6. To access the Notes and Attachments of any Salesforce object, admins must enable Lets customer users access notes and attachments in Communities Settings