Have been using Ataroid and Nesoid without problem. What has worked for me is to download ROM to my computer and unzip on my computer. For Ataroid, copy .a26 file to a directory on phone or for Nesoid copy .nes file to a directory on phone. Next I run Ataroid / Nesoid on the phone, browse to directory I coped to, and can play the games. Did have 1 ROM so far that wouldn't run, probably a dozen others that work fine.
Tried to download and unzip directly from the Thunderbolt and never had any luck, kept getting errors on the unzip. Thought I read somewhere that you didn't need to unzip the files, but haven't tried that yet because procedure I mentioned above works fine for me.