I put some early examples and tests up here:
http://starwarslegacy.net/StarWarsDS.aspx
They do not represent the finished project, but do show a bit of what is to come.
As you can see I managed to get 3D floors working on the DS without Slow Down. Also I have included a couple sections with translucent walls that can not be walked directly up to, and therefore do not slow down the game much if at all.
These levels are not textured propper as I will wait to do that last before final release, also the enemy lay out in the Space Station Argento test is random as I merely dropped a few in there for something to do while roaming around the level. Also I've not finished the Deh/Bex coding for the enemies and weapons yet so not everything is acting as it should yet, and since the gfx and sounds are not yet complete some things are still DOOM, but I think you get the idea.
Also the Mach 1 demo is ment to show off how I intend to put the player in many situations that can not be resolved by fighting, but by refering to other means for escape, so in this level in order to escape the approaching Mach 1 droid, you have to run down the hall way only to find the door locked, but if you shoot the panel (Return of the Jedi), the door flies open.
I hope to include little things like that, and bits of comedy that pay homage to the films, and most of all the books which far surpass anything that has been put to screen!
P.S. This runs betters on my GBAMP v2 than my M3 Simply for some reason, though both are fully up to date. So I think Wintermute was correct in saying that shady DLDI code might have an effect on crashes.