I was disappointed though after trying to play this game using the limited user input of the DS, you can either use the dpad with really limited control, or use the touchscreen and get one monster of a handcramp!
First I found myself cursing the designers for not adding an analog stick to the DS, I know that they wanted to encourage something different, but geez!
But lately I have realized that it was a good idea, as the DS is not loaded with all the crap games that the GBA seems to have these days, you know what I am talking about, just stop by your local wal-mart and take a look at the $19.95 games bin. Excluding SM64 and Metroid Prime the games for the DS seem to truly embrace the difference to the DS, the percentage of good games is the highest of any game system I have even known. Well I think that the VirtualBoy didn't have one bad game (I have them all), but I am not sure many people would agree with me.
But that leaves the fact that playing SM64 on the is intollerable, and it hit that it would not be that difficult to add an analog stick the DS. You see the DS uses a standard touchscreen, and the way they work is there are two sheets of plastic separated by a gell, and when you press on the screen the plastic makes contact at that point and depending on how far it is from the edge of the screen you get a diffent resistance.
The touch screen connects to the DS via a small ribbon cable, which you can see in the photo below:
So I figure that one could make a analog stick from potentiometers as long as they are the same resistance is the screen as the DS, and make a plug it in between the touchscreen and the DS, I woul think that you would need a switch to change between analog stick and touch screen. But this way you could easily add a analog stick to the DS.
I may try to do this, but I don't think it is a high priority for me. But if you do try it and if you succeed or need help please contact me