Help getting Cave Story to play on my PSP

[Yoshi of Earth]

To tell you every thing I have before I list what it does is this:

PSP 1000 model
PSP firmware 6.39
Cave Story files: data.csz
EBOOT.PBP

When I pull it up threw my games folder, it shows the background image and title of the game comes up but it say's the data is corrupt. Now I know that there is a possiblilty of it actully being corrupt, but I was wondering if it's because I'm not running a CFW? If you think a CFW will help I'll put one on my PSP, but I'd like to avoid that. Thanks for any help in advance.

EDIT: I just found out from the website I got it from that it works with out problem's on the Firmware 3.51, so I'd like to do which ever is gives me the less risk.

[Alakazander]

It will not work without CFW. For future reference, that should always be your default assumption, unless it says "signed" (me or Google can get you more information about that if you really need it).

Cave Story (or at least according to the README version I have) will only work with OFW version 1.0, anything else needs to either have a HEN (Homebrew Enabler) or CFW. Also, the README says that it will work with no modification on any 3.XX CFW (probably what the site meant).

To answer your next question, installing modern CFW is about as risky as updating the OFW, no joke. It is astronomically less risky to install modern CFW than to try downgrading it to any 3.XX. There is a great guide for installing PRO CFW (the easiest one by far, all you need is the cable really) Here .

Hope that helps.

[Yoshi of Earth]

EDIT: Never mind I got he CFW, and it works now, many thanks Alakazander!