This worked almost perfect for me but I couldn't get it to run adb commands from the stuff folder so I dumped its contents (minus the adb stuff) into the platform-tools in the android SDK and from then on everything went great. Thanks so much.
I had this same problem and couldn't find the answer I wanted anywhere. I tried factory reset and formatting the SD but it didn't work. Phone isn't rooted or anything. In the end I unmounted the SD card and then I was able to install the game then...