Terrain Paint

@IreneSwift would this YouTube video tutorial be of any help? It helped me to start to understand how terrain painting works in CAW and what part the layers plays in it.
Create A World Tips & Tricks #1: Terrain Painting

Thank you so much. This is the one thing I don't like about modifying pre-made worlds in CAW, but I am absolutely no good at making worlds from a flat map. I need the terrain already done and roads already in place, at the very minimum. But Riverview Lite already has the entire terrain painted the same as in the finished world, and that doesn't work for what I want to do with it. I do use the help file, but sometimes it's confusing because I need to see what to do, not just to read about it. I like tutorials with lots of pictures, but couldn't find one for this.

Of course there is. :)

You asked how to delete it from the world, not a chunk of the map.

Painting over doesn't remove it, it just thins it out a little... You have to remove it from that chunk if you still want to use the paint in another chunk.

Use the layer options in terrain paint. With the Visualize layer option ticked the chunk will show black/white if there is any terrain paint you have clicked active.
Having the Color Option to 0 means it will erase the paint. Any higher will add that much paint to the map.

https://i.imgur.com/aj75RWo.jpg

The Individual Layer Mode will not show black/white but will add/remove the terrain paint from that layer without messing with the layers above it. ... :)

Does this mean that there is no way to erase it from one area, while keeping it in another? If I paint over what's already there, I end up with too many terrain paints there. But if I delete the entire layer, I lose the paint too, and can't use it again.

Of course. :)

If you want to get rid of it all- that one paint layer- you can delete it from the world . Check out the Tutorial for info and Tips on CAWs page- https://www.thesims3.com/content/global/downloads/caw/help_en.pdf