The reason Dragon's Lair was not booting was because I did not have pin 17 (the Enter signal) connected. It was just a dangling wire coming from the dragon's lair hardware. The LD-V1000 manual made it sound like this pin wasn't used anymore so I didn't think that it mattered if it was connected, but I had eliminated almost every other possibility as being a potential problem so hooking up the Enter signal was one of the last things I hadn't tried. The reason I hadn't hooked it up earlier was because I had made the wire too short so it was inconvenient *embarrassed grin*.
If someone with dragon's lair schematics and time on their hands wants to figure out why this line needs to be connected, I would be interested in hearing about it. :)