Glad to help. This forum is frequented by the most helpful folks around. They've given me tons of useful info that I'm happy to pass on. I'm not the best at photoshop. I suck at layers, which is one of the most useful tools. If you check some recent and earlier posts you can find some alternate backscatter removal methods using layers. Search in the Tips and Techniques forum and you'll find a wealth of photoshop stuff. There are also a couple of books on it specific to UW photography. One is by Jack and Sue Drafahl. They have a website dedicated to UW photography learning, and years of instructional experience.
Jack and Sue Drafahl, Digital Underwater Photography, Photoshop and Lightroom Instruction
Jack and Sue Drafahl, Digital Underwater Photography, Photoshop and Lightroom Instruction