This is interesting that you haven't been able to get Download Play working with YSMenu, I haven't had any problems with any of the games that I have tried with download play.
Hmmmm... *very* interesting. Perhaps there's a problem with ysmenu loading ROMS trimmed with... oh, for the life of me, I can't remember what it's called. BrianTokyo's tool - the one with the soft-core backgrounds.
The official DSTT kernel has absolutely no problems with download play from those trimmed roms.
I'll have to try again, with some untrimmed ones, then. And I'll update to the latest version of YSMenu while I'm at it - I'm maybe one or two behind by now. Thanks for that info.