Yeah, me too. I've only played through the PS2 version although like many ports on the system, it looks like crap. I own the DC version as well but it's one of the few JP games that doesn't run through the DC-X boot disc. I wouldn't really want to play it again though since it wasn't one of my favored titles (along with a bizarre development towards the end...).
Alright, so here's the SPC-1000 emulator stuff. I've been meaning to post this after translating the mySPC readme into English, but seeing how I'll likely never get to it, I just translated the hotkey portion and uploaded all I have:
How to run: Upon every start you have to select which bios rom to load, but I only ever found the SPC-1000 one, and even that doesn't seem to be the correct one, but it works.
After inserting and running a tape (see instructions) type LOAD, some games autostart after that, for others you have to type RUN, too. A few consist of both basic and machine code portions, in those cases you have to type LOAD twice. For Lunar City, you have to insert the basic side, type LOAD, insert the machine code side, then type LOAD again.
You might want to switch off scanlines before running the tape, afterwards the key is deactivated. I don't think there's a x2 display option, though. To make the view bigger, you'd have to switch to full screen mode.
The directional keys to control the games are all over the place, sometimes it's J/K/R/F, or G/H/A/Z or whatever. The action key is almost always space, and shift for games that use two keys.