Ha, just mentioned this in the ORCA thread before realizing it had its own thread. Right now, I'm just eager for the Uxn version to get a gate parameter on its MIDI operator since, currently, it only works as expected on drum machines or devices which function similarly to drum machines. I've got the means to try it on GBA and DS right now and will be taking those for a spin before too long. I'm also hopeful that the GBA implementation can get keyboard input before too long, although I'm interested to see what they come up with for controller input in ORCA. (hoping for contextual value cycling, though button combos would surely work well enough--would also love to see value cycling available with key combos on a keyboard)

I reported to forum, Internal synths fixed, but it still play irregular notes. Anyway there's not much to do with synth implemented in Orca yet, maybee later there would be some more complex instruments implemented in UXN versions?
I tried to run Orca for past few days, unfortunatelly I have only 32bit Win system, so there are no standalone versions of Orca.. But I did managed to run web version nicely in my Opera browser. Shame that I have to use some VST instrument for sounds (there are no 32bit versions of Pilot or Cassetter). Didn't get to this for a long time, so...

I got it working but not really managed to do much yet. Some of the music roms don't work properly in that the screen is cropped. Need to have a proper play soon. Been meaning to learn Orca anyway as I can use it on Norns too

Did you get it to work?
there are different releases for 3DS and for NDS...
and there is readme file..
https://github.com/asiekierka/uxnds
If you like to run ORCA, download it here:
https://hundredrabbits.itch.io/orca

Yeah, you're kind of limited to internal synth wich should have 4 sounds, but only 0 works for me
use command:
= 0-3 (sound) x (octave) x (note)
but it doesn't seem to work properly, it skips notes / play irregular notes from T (tracker) command

Uxn is a portable 8-bit virtual computer which can run on all manner of portable/small/obsolete devices including Nintendo DS! I discovered it from this thread on Lines which has lots of info and links. Haven't got properly into it yet but looks promising and there are a few music roms for it already:

https://llllllll.co/t/uxn-virtual-computer/46103

Here's the DS version, in the above thread there's instructions on how to get it working (long story short you need to rename the rom 'boot rom' for the DS version), I wouldn't have figure it out myself https://github.com/asiekierka/uxnds/releases

EDIT: just managed to figure out how to download a bunch of the roms without having to compile them or whatever https://github.com/aduros/webuxn/tree/master/roms