Getting started

This is my first time using StarDog. I have good IT skills and an understanding of relational databases. I've created an ontology in WebProtege, that I have exported and then successfully loaded it into a StarDog system at the University. I was able to run a few queries that are found in the tutorials that show me that it is functional. However, to be able to use this for my research project, I need to be able to create specific SparQL queries and run them to extract data and verify some of my hypotheses on own the ontology can help extract knowledge and answer questions.

I'm trying to figure out the structure of the data (data model) once the data is loaded and how to formulate my queries within the dataset. I'm been going through the manuals and the videos but I feel a bit confused about how to get started and how to extract information from my ontology.

What are the recommended way to get started?
How can I get information about the structure of the data I have, once loaded into StarDog?
Is there some kind of quick reference guide to StarDog commands and variables?
Other than the YouTube Tutorials and the docs pages, what are good resources for someone getting started?

Thank you