Well, I've been thinking a lot about the ability to use a DX ROM on the D2. As I was thinking, I remembered a file that I used to use on Froyo that allowed me to use DX ROM's on the D2. That said, I don't have the time or patience to try it right now. You flash the following file in bootstrap after flashing the ROM.
Also, I don't remember who created the file, but I think it was someone from the GummyJar team.