Do an s1clone dump and make sure it is correct and you can write it back to the player, before you try any other experimentation... also unless you are sure it is a SCC91-002 with a CM60026 (open it up and look at the board ID and LCM part#) and AK1025, don't continue.
Otherwise, this seems to be the exact firmware for your player. The description matches, and from looking at the picture you also have a
ping guo er dai.
http://www.s1fw.com/Firmware-1/LG-LW...gai---rar.html
If you want to change theme you can try s1res on this firmware.