I forgot to mention in the cave intro texts that cave M (Millionaire) is actually a standard size version of Arno's "The 2 Million Challenge" YouTube Video! I always wanted to make a cave with a lot of diamonds to collect for the Dustin's BD series, but I found all my own ideas unsatisfactory. Then when I saw the video, it struck me as almost perfect for my purposes and I basically just rebuilt it for this game! :D
Have fun playing the game! :)