Using YARG, what band do I use with multiple SQL statements

Looking at the documentation I’m completely lost. I’ve created several YARG reports using the wizard, but without using the wizard I’m completely lost. I have a long list of SQL queries for one report, many of which join tables together. I need to generate a report, but “trial and error” isn’t working and I don’t understand the documentation I can find because what I can find is not very intuitive compared to other report generators. Do I need a “band” with SQL type queries? Can I use YARG to generate a template when not using an entity or list of entities? What do I have to include in a custom template to get the ${variables} to populate? Why do I need an XML file? Did the wizard create that for me when I was using that?

Ultimately a step by step tutorial (similar to High productivity application development platform starting on page 108) for creating reports WITHOUT using the wizard would be fantastic.

For now - I have a list of queries that hit multiple tables in the database that need to be populated in a single report. How do I do this with YARG?

Found this. Thanks!
https://doc.cuba-platform.com/reporting-6.3/creation.html

(I feel kind of silly. How did I miss this?)