Before, I was having trouble with custom loading screens for the extend. But just recently I found the key to it if you're having trouble with it too because it now works for me. First, have the image itself be 480 x 272 in the center of 512 x 512 transparent. You can add the transparent part with GIMP. Now the key for it to take effect is for you're image to not only have the same name, but for it to also be the same file size as the loading screen you're replacing. And for that to happen is to definitely use TinyPNG, and I also used PNG Compressor. https://tinypng.com/ https://www.giftofspeed.com/png-compressor/ You want the result from using these two links to be smaller than what you're replacing. And to bring the file size back up for it to be the same is to use Hex Editor Neo. Go to edit > change file size. Once the name & file size of your own image is the same as the loading screen you're replacing, on your PSP place the image under SEPLUGINS > divapatch > divaext. It should work now ~__^
Funny thing is, SonicDX made instructions for this, and it says it has to match original loading screen file size, and I didn't notice that XD
Another funny thing here is that I had no idea that SonicDX made his/her own instructions for this. Before, I was reading the instructions from this page and it doesn't mention the file size. https://projectdiva.wiki/wiki/Custom_DLC_for_2nd_&_extend_(Discontinued) I actually figured this out myself. And I was excited when it worked that I was like I had to post what I did for it to work on here for others ;)