I tried to see if the bottome screen displayed anything on Phoenix Wright games, but still no luck.
I wouldn't bother testing much though, since improvements seem to be from areas that don't improve compatibility much.
The features implemented are such that getting compatibility later will be much easier. It's the kinda things that are more backend type fixes such as CPU fixes, GPU optimizations, and MMU fixes. Without these fixes, it'd be much harder to tackle the graphics situation later. Think of it as a precursor.
i believe if u really wanna try a good nds emulator then it has to be no$gba
as i tested it can run the ffIII movie sequence and a little bit of the ingame graphics (still no cigar)
Contact me thru email if u want no$gba