I hope that this won't sound rude to you, but... Some things are so easy and self-explanatory that you don't even need to search for a tutorial, since by just exploring the program a little, you'll quickly find the answers. This is one of such cases.
Remember to always explore the program before turning mad looking for help! You'll save yourself time and effort.
I'll just tell you that by going to the Database and the Resource Manager, you'll be able to configure ALMOST every setting in your game. Now, if you are looking for custom resources for the game, you'll have to either search around the internet and RM forums, or make your own. To add it to your game, you need to import the desired image through the Resource Manager, then go to the Database and, in System, apply the image in the right area.
Good luck!