Tracking multiple maps on a domain is easy. You'll simply need to follow the same steps in Step 2.
The final step is to make your map aware. You just need to add the following two lines after your library, but before your code, this order is important. This example is for leaflet, but if you're using something else, the setting page will give you examples for them too.
The following table shows our rules for file naming between different libraries. Plugins follow the template: