As @RagnarLothbrok pointed out, it’s less dense, more focused and is best used for those who want to commit to a tighter stack (or single title).
Except instead of a CORE (which has some of the support scripting removed in order to make it fit the custom process), this is the full sub, exactly as it would be as if you were just running the major title, except customized. Even though the UI may say “Core” (since it’s just pulling from the product database), Q-Engineer will know to use the “Major Title” machine from the BUILD item on the order receipt.
No. The scripts used for the major titles are much longer than the Cores on the Q store (hence why it’s a core, it contains all the core scripting for that title). These use the exact same script from the major titles. The extra module allows you to customize the title and add some functionality to it.
If you want to consider it a “custom light,” however – that’s fine.