Just run the *.ds.gba version in no$gba. It mostly works just to get an idea of what it does.
But by god, I haven't heard the names "DarkStar" "DarkainMX" and "Lynx" in YEARS. You're looking at one of the oldest homebrew programs available for the DS, so getting it to work on any slot-1 program might be a challenge. In fact I'm not even sure if you can even convert the *.ds.gba version to a workable *.nds file, since it was probably compiled before the two formats were more-or-less identical.