I've taken SMSSDL and ported to the native dingoo firmware using flatmush's superb SDK.
Its only a beta so there is no menu yet, just a sim which plays SMS or GG games fullscreen with the sound on. I'll add a menu later which will allow you to tinker with the settings and manage your save states etc.
Download from the link below.http://reesy.gp32x.de/smssdl.tar.gz
Source code is contained in the file above for those of you who are interested.
The rest of you just need to take the smsplus.sim file and put it into the GAME folder on your Dingoo and then update your jukebox.
NOTE: You'll need to remove any existing SMS/GG emulator you have in the GAME folder as I have no idea what the Dingoo firmware will do if it finds 2 SIM files which support the same file extensions.