1. I don't have access/can't add "Shape-Warehouse-####" as a data source to Data Studio
After you create a copy of a Shape template report and select the BigQuery connector, you should be able to add your "Shape-Warehouse-####" as a data source to Data Studio. If you cannot, this is likely due to a permission error.
The most common error occurs when a company uses Google GSuite for their emails and has rebranded (or added alias emails) at one point in their history. BigQuery will default to using the original GSuite email even if that's not the current email used.
For example, Shape was originally named SteadyBudget. Previously, our email was email@example.com. When we add new team members to our Data Warehouse, BigQuery automatically defaults to using firstname.lastname@example.org even though our emails are now email@example.com and the @shape.io emails are what we use to log in to shape.
If you go to the ADI "Access Control" control page, and cannot grant your current email access to your Shape Data Warehouse/BigQuery, this is likely the cause.
If this is the case, add your email (with the original G Suite domain) as an "External Contact." You should now have the ability to access your Shape DataWarehouse in BigQuery and add BigQuery as a connector with your primary email.