As the one who started this thread and then left on a 10-day business trip, I was amazed to come back and see how many others had had issues! Thanks to reading all of your posts, I was able to run CCleaner, install the game in Safe mode, and change my screen resolution, and it's playing just fine now.
Seems like ridiculous lengths to have to go to to make up for sub-par game development and customer support, but I guess all's well that ends well. I hope the rest of you are able to get Dead Reefs up and running too, and that you let TAC and the developer know politely (as I did) about your experience.