Okay well, this is last you are going to get out of me on this subject, here is how to change a copy of 
PC Engine Best Collection: Ginga Ojousama Densetsu to play other games (there are a few different
PCE best collections but this is the only one I have, details should be similar but different). Hopefully
this wont go against some arbitrary piracy policy :)

First pick up a copy of the game, check out PlayAsia, only $30 or so. So you have bought it, right?
Okay well use something to convert it to an ISO, obviously if you could modify the UMD life would be 
simple. Now get hold of your PCE CDROM game and rip it to ISO/WAVE/CUE, the audio tracks must be 
wave files, the ISOs (which there are normally two of) should be MODE1/2048. I am not going to 
explain how you do this, it is fairly simple :P You must have a valid CUE sheet for this as it is
needed by the converter tool to work out offset information.

Now you must encode the audio, the game uses Atrac3Plus it seems but the only freely available tools
spit out Atrac3 so we will have to do some hacking, anyway use something like the Codemasters EAC
converter to convert the wave files, you should end up with a load of .toc files. Don't delete the 
.wav files though as they are needed by the converter.

Now use the converter tool attached to this post to convert the files. Run the pceconv.exe tool from cmd
passing the path to the cue sheet as the first parameter and a path to an output .HCD file. The file
needs to be named appropriated, so say we are going to convert our game to replace Yuna, issue the 
command: pceconv.exe path\to\file.cue output\HCD5078.HCD, note capitalisation is important, the HCD
file must be in upper case otherwise it wont work :( Hopefully the tool should now go off and process
the files. It will compress any ISO files and copy any .toc files to the appropriate names in the output
directory. Oh yeah you will need .NET 2 installed to use the converter :)

Now time to put it all together, open the ISO of the UMD in UMDGen (or whatever you want). First replace 
the files under PSP_GAME/USRDIR/CONTENT/CDROM/HCD5078 with the ones you converted, this means that 
Yuna is now replaced with your game. Now if you have used Atrac3 to convert the audio you need to modify
the main executable. Extract BOOT.BIN from PSP_GAME/SYSDIR and apply the boot.bin.ppf file to it.
Replace in the original image the BOOT.BIN and EBOOT.BIN with this file. 

Now output an ISO, copy to the PSP and run it. Choose Yuna (the first game it shows) and hopefully it works.
I have managed to use this method with Dracula X, Rayxanber 3, Art Of Fighting, Strider and Nexzr successfully
and I am sure other stuff will probably work. 

Have fun!

MacTheFork 2k8
