PSP ISO wont load properly

I've got an issue with two ISO files that I am attempting to run off a memory stick. The games both load past all the initial auto-save and game publisher screens, but then wont load any further. One of the games is 'Darkstalkers - The Chaos Tower' which loads until it gets to the "Now Loading" screen where it ironically stops loading.

I have a PSP 1003 equipped with 5.00 M33-4 CFW on which the rest of my ISO's and CSO's work perfectly. I have tried booting into the recovery mode and switching the kernal between 1.50 and 5.00, but neither allow the problematic ISO's to load. Maybe I'm missing something or maybe the two ISO files are corrupt - although I have downloaded the ISO files twice and they hang in the same place on all versions?

I'd really appreciate help to solve this issue. The not knowing why is won't work is almost keeping me up at night! Many thanks. :)

I'm sorry but asking how to load commercial ISOs/CSOs is against the forum rules as it's marked as warez. The store is where you really should be getting your games from.

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