Hm, never had that problem. Make sure your roms have the file endings .smd or .gen or .bin. You unzipped them right?
Oh, maybe you just missed this: It doesn´t matter where you put the roms, but: You have to navigate to the folder you put them into when you first start up jenesisDS´s menu.
And I´ve read that some people have less problems with 0.7.3. Maybe also try that?
Hopefully one of these advices work.

This post has been edited by Guy.brush, Fri, August 26th, 2011 at 17:20