no, the rev21 update IS already updated : d2x is an update of rev21
that's why it's version "21 008" it's the 8th patch applied to rev21.
You can leave your slot250 like that, it will not conflict with the other installed slots.
though, just remember that your slot250 is not "common", so if one day you see someone giving suggestion to "use slot250" to fix a game, don't follow that advice.
most people are softmodding their console differently (installing a "base57" in slot 250, and using 250 in priority instead of 249).
I made you install base57 directly in the default slot, you already have the best one so you don't need to change the slot number to use it.
btw if I want to make another virtual memory card do I have to do it through nintendont? or can I somehow do it through USB loader GX? regardless the flash drive I got seems to actually be working now unlike my HDD.
The memory card used by Nintendont are generated by Nintendont itself when the game is launched. (it may take few seconds at first game launch)
the memorycard image is generated on the same partition than the ISO, in /saves/ folder.
there are two memory card emulation type :
- Multi (or ON in USBLoaderGX) : it uses a single memory card file with all games in it. it saves "multiple" games on it.
- Individual : It creates a private memory card per game. each game has its own savegame file.
I suggest using "individual" with 251 blocs. (should be the default size)
some games are not compatible with bigger cards.
using "individual" option will prevent you from having a full memory card as each game will use a new, empty, card.
if the memory card is corrupted one day, only that game will be lost, as other games are not using that file.
Advantage of Multi is that some games are "looking" for other savegames to unlock features.
for example, if SSBB see you have a savegame of Zelda twilight princess, it may unlock Zelda character in SSBB ! (that's just an example, I don't know if this example is actually true)
to do that, you need both saves on the SAME memorycard, and thus using "multi" is required.
USBLoaderGX let you choose whether to use "Multi" or "individual" on a game by game basis.
I suggest you set the global setting to individual 251. (in the loader settings)
then, for games you specifically want to use "multi" to share the same card, just select the game, go to option, game option, select "ON (multi)", and save the game setting.
for just this game, it will use a different settings than the "global settings set in the loader".