From what I recall...
You have to first put the pec plugin into the ePsx plugins folder. Then in ePsx set the pec as the video plugin and configure it to use a regular graphics plugin.
Then close ePsx and start the emu cheater. Activate the cheats you want and send them to the plugin, then start ePsx.
That's the way it should work...
Dunno know if it makes any difference if it's running off a CD or an iso. You can try making a virtual drive with the iso and see if that helps.
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