You need rcomage, it can extract and compile rco files.how can i edit this .rco file?
It has issues with repacking images into ps3 rcos though, so when extracting untick the box for "convert gim images to png" , leave the other settings on default. If you want to add or edit images that is trickier as you need to use gimconv via cmd.
The mod I did was not an image mod, those emojis and icons are a text mod of the epilepsy warning using imagefont.bin characters.
Then it will extract the files into the folder set, you will find a load of language xmls in there, here you will find all the text entries that are displayed on the XMB. If you are releasing a mod you should edit all language files with your mod, if its just for your own use, you can just edit your own language xml. Note for English there are 2 xmls, one for UK and one for US (US one is called unknown12 I think).
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