Have some answers, my good man!
1. Is there any Custom SSS code that maxes out the stage list? I saw a code but I'm not sure where it was.
I take it you already found this? I was browsing the thread the other day and saw a code that does this, I assume that it's the one you used?
2. How would you replace the extra stage itself? I don't understand this.
Well first and foremost you need a method of getting the game to read files from your SD card as if they're on the disc; this -might- be possible with the File Patch codes but it's easier to just use Riivolution for that. If you're using Bionic's modloader.xml [I haven't even looked at the others] you'll have to either add lines for loading the stage files yourself or use the updated version I posted in a few threads.
Once that's done you'll want to rename your downloaded stages to match the spaces that you've put on your character select screen, with the format being st_customXX.rel and STGCUSTOMXX.pac with XX being a number from 0x00 to 0xFF. If you select an icon on the screen that does not have a corresponding set of .rel and .pac files then the game will hang as it tries to load a non-existent file.
Does this cover everything? This is kind of a huge question so I just covered some of the basics to get you started.
3 What if there's a stage only that can be replaced on Final Destination only? How would you replace it on the extra stage?
That's easy! Grab a st_final.rel from
this topic (It's in the Mediafire archive under the fifth page of the "module" directory), then rename it to st_customXX.rel, with XX being the numbers to match whatever you named the stage's .pac file.
4. I think Phantom already said this in the thread, but still... is it possible to add any custom icons to extra stages?
From what little I've played with Brawlbox it's possible to add a new texture to sc_selmap_en.pac and rename them so that they would appear to be number 60 [appears to be base-10?] and beyond to the game, but I haven't really looked into it beyond that! In theory you should be able to add the needed textures then increment the icon number in the code accordingly but I haven't tested it yet so I don't know if there's a hardcoded limit or not.
I will really appreciate some answers! ~_^
You're welcome, man!