I just purchased Ghouls 'n Ghosts (Dai Maikimura) from the Japanese shop for the Super Grafx. As expected, it's has the standard PC Engine banner, and Super Grafx mode is enabled by a simple flag in the ini file. I've confirmed this by getting the game running in a standard PC Engine wad.
Here is the 'config.ini'
Code:
NAME=N43800AL
ROM=/LZ77N43800AL.BIN
BACKUPRAM=0
MULTITAP=1
HDS=0
RASTER=0
POPULUS=0
SPRLINE=0
PAD5=0
NOFPA=1
SGENABLE=1
The last line there enables Super Grafx mode. LZ77N43800AL.BIN is the (compressed) rom. It's funny that there is also a second compressed rom, LZ77NC92003.BIN inside the game's 005.app! I uncompressed it and found out that it's Tower of Druaga!
Since there were only 7 games made for the Super Grafx, I went ahead and made wads of the other six. I also made custom banners and manuals in English with Super Grafx logos made as how they might appear should the system had been released in the US. Here are the games:
1. 1941: Counter Attack
2. Aldynes
3. Battle Ace
4. Darius Alpha
5. Darius Plus
6. Ghouls 'n Ghosts
7. Granzort
Granzort is actually called Madou Granzort or something like that, but I just dropped the first word for it's possible English title. The Darius games are actually normal TG16/PC Engine games that are enhanced when played on a Super Grafx. Here is a zip file containing all 7 custom English banners I made:
http://www.mediafire.com/file/yoggm32inyr/SGX.zip
And here is the custom manual for the 6 games besides Ghouls 'n Ghosts, which I just kept the original Japanese manual. The manual is very simple and only has a Super Grafx logo with two pages, button key, and suspending. I merely changed the title on each game.
http://www.mediafire.com/file/yoggm32inyr/SGX.zip