Nah, it's not the CHD; you wouldn't get that kind of error if the CHD were corrupt. It's a different issue,
and it's hard to guess the cause—there are so many possibilities: folders or files in the wrong place or named incorrectly,
whether `acgame` points to the right files and is written correctly, whether your ELF files and memory card files are valid and named with the right extensions,
and whether the emulator's game list is set up properly. Also, make sure you have the "portable" file in place before launching the emulator for the first time;
otherwise, it'll create files in your `C:\Users` folder and so on.
I'd recommend starting over with the Emusempre pack—you'll have a working version right off the bat and can start figuring out how it's all put together.
That's what I did; otherwise, I would've been stuck too.
Take some screenshots so I can understand and see where the problem might be—if I spot one.
Include the folder structure, the code from the `acgame` files, and the emulator running with your game list.