I just started to begin with DSi Emulation, using lr-LemonDS, and came to the point the tutorial ends: games will only start via the DSi-Menu, so "boot directly into rom" has to be disabled in the core-options.
Only difference: i have full access to the DSi-Roms in the /ROMS/DS-Folder from there and dont have to use prestuffed NAND-Files (would also be a fishy way imo, not the way it should work)

And this is an issue:
first of all on the official FAQ-Board it is recommended to keep this option at its default (=off/boot into rom), in special when the DSi-Bios is used.

Secondly the Retroachievements for DSi-Games only launch up when booting directly into the rom, you can see the widget, everythings fine.
Only problem: the screen keeps being white and silent.

Booting into menu works as mentioned, so the BIOS-Files are good for sure.
I can start all my games from there, but without Retroachievements Support, so i hope to find a way to boot directly into the game (as it should work :)).
I allready tinkered with further core-options, but had no luck.
If anyone has an idea it would be much appreciated.

@sleve_mcdichael Thanks for your help with this, you're a star. Oddly $system doesn't want to play ball and reports back empty, so I just changed that to nds directly and it works fine. Have added a PR into RetroPie Extras if anyone is curious to see the end result.

Oh also the core has networking support and works fine playing on wiimmf if anyone fancies a game of Mario Kart

@ranma I worked on an install script for it once. Would you be willing to show yours? I would also like to know if your using drastic bios or the real deal. Did you emulate DSI?

Has anyone tried it more recently?? I was just curious to know if after more than one year it got better in performances...