Make your PSX Games Work with a customized "Coldboot( Text, sound, wave, etc) or any combination of the three"
Ok I'm going to explain how this works, As you have noticed, to have a customized coldboot requires a decrypted "opening_plugin.rco" file from a 2.5 or 2.6 firmware dump.
Since we are using a lower firmware file, PSX Emulation will be broken and you wont be able to play PSX Games at all. We can't customize our own 3.02 or 3.03 or 3.10 "opening_plugin.rco" because from 2.6 onwards Sony started to encrypt them. Hence making them impossible to customize. Thats why we need to have a 2.5/2.6 "opening_plugin.rco" or theres no coldboot at all.
Lets get started now:
Requirements:
1. Any Hex Editor; to go well with my guide use "Hex Workshop 4.2" which you can get a FREE TRIAL at:
Hex Workshop FREE TRIAL link (download.com) Supported Firmwares:
3.02 OE-A
3.02 OE-B
3.03 OE-A
3.03 OE-A'
3.03 OE-B
3.03 OE-C
3.10 OE-A
3.10 OE-A' (Rev 2)
3.30 OE-A
3.30 OE-A'
3.40 OE-A (Tested by me)
NOTE: 3.10 OE and 3.30 OE users can easily do this mod without hex editing; either way you can but this is a lot easier.
LINK:
LOLstation -POPS-Fix Will this brick my PSP? NO. the one thing that might happen is you messing up the "hex editing" and having 'no psx emulation' even after doing everything. if this happens re do my guide again.
Files needed:
======================================= 1.
Modified:2.5/2.6 "opening_plugin.rco" (with coldboot sound, tex, etc) Your customized coldboot Brittany or you made.
2.
untouched: "opening_plugin.rco" from your firmware dump (3.02 / 3.03 / 3.10) or from flash0.
Location: flash0/vsh/resource 3.
untouched: "game_plugin.prx" from your firmware dump (decrypted files).
Location: Flash0:vsh/nodule ======================================== Procedure
1. Rename Untouched "opening_pluging.rco" as labeled in requirements to: "
0pening_plugin.rco" -
NOTE: 0 = Zero
2. Flash it to "Flash0:/vsh/resources" after you rename the file.
3. Open "game_plugin.prx" with a hex editor (Hex Workshop) and go to offset : <<
1372C >>
*** UPDATE ***
Offset for 3.40 'game_plugin.prx" =
16B8D
I took this picture and it has every single STEP you need to do to accomplish it.
NOTE: just keep the whole path untouched and change the "o" to a (0) Zero.
4. After you have saved the modified "game_plugin.prx" Flash it to:
Location: "Flash0:/vsh/nodule" 
Your DONE !
Conclusion:
1. Customized (2.5 / 2.6) "opening_plugin.rco" Will have your customized coldboots
2. Untouched (3.02 / 3.03 / 3.10) "opening_plugin.rco" will play your "PSX"
Enjoy your coldboot and your favorite PSX games
!
Mime...