I'm a little confused about what needs to be removed, nil'd, etc, and what is automatically cleaned up by any built-in garbage collection.

I see that when using the Director Class that I use a cleanup function and usually do a removeSelf on buttons, images, etc. Except, do I not have to do this if they are in the localGroup that is returned because Director cleans those up?

For NON-Director matters, if I define a table in main.lua that I use throughout the game, and it's global, is there some kind of onExit anywhere where I need to cleanup these global variables?

If there are already online tutorials regarding this, I haven't seen them yet, and would appreciate any direction you could provide. Thank you.