You play ISO/CSo files by upgrading your psp to CF. I am not sure about his link....but all you need is a Pandoras Battery and MMS to put CF on your psp. The Datel Tool Battery does the exact same thing as the Pandoras Battery.
If you use these files and guide you will not have to use whatever guide was in his link. Just download these files install them on your MMS following the guide and use it with the Pandoras Battery. Here are the files you need:
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