uPCE does run disk games, but there is no mp3 or CD Audio support.
Before the other forums died, I'd asked Uguru if this was something he planned to support in the final version of uPCE, but I'm not sure if he ever replied as the forums got wiped.
Given the Dingoo needs to be overclocked to run smooth even at Frameskip 1, unless he's got a load of optimisation that can be done it might be something that is too much strain. It'll have some hit to decode wav or mp3 whilst also emulating the system. Likely the same for Picodrive too.
I suggested maybe they could implement Ogg playback though, I'm pretty sure that's quite light, but it would mean you'd need to convert the mp3's over to Ogg.
All I did to run CD games by the way was to copy syscard.pce to the same folder as uPCE. You're best picking up the System Card 3.0 rom for this - some games will work with earlier System Cards, but not all. The System Card was effectively extra RAM for the PC Engine originally - as well as holding the libraries to load and run CD's. That's why you need it ever for an emulated system.
I admit I've only tried DraculaX too - but it does run. Don't think it's saving the games right at the moment though - which is a pain as you have to sit through the intro each time you want to play (this was the case when played on a real PC-Engine, it won't let you skip the intro unless you've made a save!).
I was hoping Hugo would play CD games too. It does include System Card 3 - but I couldn't figure out how to get it to load the cue/bin I've got of DraculaX. I know the Windows version supports CD games. Might be it needs an ISO image instead... I'll give it a try when I've got some free time