Here's a demake of Karuga currently in development by matref for PC.
It is completely in 2D and reproduces the core gameplay pretty well.
It was originally a game for the Ti Nspire CX but later decided to focus on PC instead.
He still kept using the software renderer that was used for the calculator.
As i ran into some disagreement with him, i forked his game and in the process,
i made a GCW0 port.
Here's a video of it running on mah zero :https://www.youtube.com/watch?v=SgYq9c3b9U4
And you can download the game here :https://github.com/gameblabla/nKaruga/releases
Installation is simple :
Decompress the zip and put the OPK file in /media/data/apps/
The game has only 2 stages out of 5, as he still need to finish the game.
The GCW0 port works well but has some usabilitiy issues so don't try to mess up with it.