Emunand won't help. It will allow you to install more games that appear on the Home Menu. But games not installed to SYSNAND TWLN will lead to:
An error has occurred
Press and hold the POWER Button
to turn the system off.
Please refer to the Operations
manual for details.
Seems the NAND redirection is not working when loading TWL_FIRM.
There is currently no way around this stupid limitation on the 2/3DS. Robz8 mentioned at some point (hope I remember correctly!) nds-bootstrap does not support loading DSiWare at the moment. Perhaps in the future.
On the other hand: A DSi with Unlaunch 0.9 or later can load DSiWare from TWilightMenu++