Retail games? Getting ready to make my own CIA, so I'll report back if it works.
Homebrew? BlargSNES, GameYob, and CitrAGB all works.
You must have some form of DS flashcart (you might get lucky and use a Gateway-encrypted launcher.dat and use the browser exploit to load it if you're on 4.5, but I, for the hell of it, tried to use GW2.7's launcher.dat and it consistently failed). Other than that, you still need a flashcart (at least it's a DS flashcart, and on 4.x of all system versions).
Basically, I:
- backed up system's SD card
- downgraded (obviously)
- configured the microSD card for the blue card (using 3.0.1's blue card files) to install the mset exploit
- used the blue card
- formatted emuNAND
- copied Launcher_GW.dat to the root of the system's SD card (renamed as Launcher.dat)
- used emuNAND tool to back up the emuNAND (not necessarily a backup, but it's needed for making redNAND; you can use your 4.x NAND backup if you want)
- used drag_emunand_here.bat (
in the linked post) to create redNAND
- used emuNAND_tool to inject redNAND into emuNAND
- copied system's SD card's backup back up onto the SD card (since the *.db trick failed for me)
- went into DS Profile to trigger the exploit (while holding L) to boot into redNAND with the ctrserver
going on a limb it's called that, since there's ctrclient
- used wnetwatcher to find my system's IP (I configured a static IP, but I did that after the emuNAND backup)
- executed run.bat with corrected parameters
- enjoyed the DevMenu/BigBlueMenu goodness
Needed the Palatine's CFW pack, emuNAND_tool, and the redNAND maker (drag_emunand_here). No need for win32diskimager or hex editing.