I started to port Daniel Coulom Thomson TO8D emulator (http://dcto8.free.fr/dcto8d.2009/dcto8d_fr.html
) to RG350 handheld.
If you are interested in beta testing, it is available here : https://github.com/goldmojo/dcto8d/releases
The current beta version permits to load fd / m7 files (avoid k7) and a minimal set of keys are mapped. Both joysticks are fully mapped. The full user manual is available on Github page.
Next step will be to add a virtual keyboard. Do you have a proposal of available keyboard code I could use ?