Okay, for those who are still looking at this to work, don't bother. Everything I've seen on this thread points to the nds file not working on many homebrew cards, and having severe issues with needing to convert both dance and music files to be compatible with the game.
use this link instead:
or go to the site directly via:
DSDSRevolution is from a japanese site, but it plays pretty much flawlessly once you have everything set up properly.
The only issues is that it can only play .sm files and .mp3 files(though support seems to have been added for .ogg files in v0.4.4), it can only handle up to 32 dance files at a time(this willl likely be addressed soon), and the default controls are weird, so you'll have to modify the DSDSR.ini file(found in the DSDSR folder) either on your computer or using DS organize or some other text editor to suit your preferences.
In order set it up, you put the DSDSR folder on the root of your card and nds file anywhere you want. in the DSDSR folder there will be a folder named Songs, in this folder, create a new folder with whatever name you feel like, and then in this folder you created, place the individual song folders that contain the .mp3(or .ogg), .sm, and .bg(not required) for the song.
Unfortunately, if you place more than 32 dance folders in the main folder you created, some of them just won't show up in the list. Sadly, you also can't create more than one folder to put your individual dance folders in.
in order to create .sm files from .dwi files, I've found this thread gives one of the simplest steps, both for converting individually, and for doing a batch convert of all your Dance files at once.