The following list summarises the operations to do to obtain a Metacosm instance.
Define ideas/concepts of the new instance
Choose a name for your instance
Extend your concept: add some background, to describe the world(s), to clarify rules
Define your rules.
Create Properties and Entities
Create Predicates and Actions
Create Quests
Test, test and test
Write some documentation
Release (and enhance and release and ...)
You can rely on Basic Instance or not.