IsoBuster 2.1 or 2.5 ?

I think the guide is just out of date; you should use the latest, final, available version. There are some mistakes/fixes on the PS2 guide, so it just need to be updated.

By the way, regarding the IsoBuster registration, if you didn't buyed the program and contrarily are using a pirated key, you should note that as far as I know there is just one "legit" and "%100" functional key available out there.

Those keys generated by the "Again" or "ZWT" keygens and others keys were banned by the software's author some time ago, and although they seems to work well (because the program accept it as valid keys and you see "Pro" version on the about screen) they aren't valid keys.

To test if you are using a non %100 functional key, just try to make an extraction from a disc with a UDF file system and/or try to make an extraction from the HFS or HFS+ file system from an Hybrid ISO disc and you could see a nag telling you you "Only available in registered version" from the program.   Moreover, you could try to fordward your system's clock some months, and next time you want to use the soft, you will get a trial period expired message when trying to use it.

Those wanting the valid and %100 working key, just drop me a pm and I will send it to you as soon as possible.

P.D. I ask you to send me a pm because I don't know if it is allowed to share the key directly here in the forum.