Rpg Maker Developers Group

Hello there, fellow Makers!

I'm currently having some trouble figuring out a couple of issues from Yami's Overlay Mapping script. That link will take you to the script I am using for parallax mapping. I am also lucky to have come across a pretty handy post someone made a couple of years back in regards to it, CVincents Parallax Tutorial. I started following it step by step to making the map, adding in the scripts, etc, but I am still unsure about a few things.

The script mentions that there are four layers: Light, Shadow, Parallax, and Ground. From what I am reading it feels as if it means that Light/Shadow changes the maps from day to night. So, does that mean that Ground is... well, what's below the player, and parallax is above it, such as if you are adding trees in a forest to walk under (but of course declining passability to the trunk)? And if that is correct... does that mean you don't need to make layers for Light/Shadow if you do not need them?

Also, I have followed the instructions and have added the Overlay folder to my game's graphics folder, but it doesn't show up as a folder in the Resource Manager when I run Ace. The script/tutorial mention that the layers should appear once they've been added in, but the folder doesn't even show up.

I have a bunch of other questions, but I think if I can figure out the answer to those two, all my other questions are going to be answered, such as why the layers don't even show up automatically. But thank you everyone for your time!