Some of the LOWER POINTS I added may not be required in the Custom 1 Depth, but this should help get you to understand how to create your own shading. I had several questions lately on how to do this and sat down quickly to help those who asked.
Yes, if you have a C-MAP chip. Check out the newest C-MAP Reveal chips. int.c-map.com/all-charts/reveal/?fbclid=IwAR2a6LbV1m0RCp6DLacFC1bqift4h23nhFVCWtOUazYhc2C9gZGfeUPpnnw