Let's say I create a template for all users (main screen) and I want to EDIT the content for all users. How can I do that without creating a COPY and then going back into all client portals and deleting the old version?

Some of these pages/templates will be shared across all clients.

Also, can we have shared files across all clients/portals too? This is essential for us. And if I can get this all right, I will be subscribing to the Agency plan (that is actually what I am testing now).

Please let me know.