Hi, sorry that I took long to reply, I wasn't around. Well, it's very simple.
You can change menuscreens by pressing should R and L. There are two screens you can see by pressing R twice when you first start the GBA Backup Tool, let me explain it:
When you first load the GBA Backup Tool, the first screen you see says:
Please set a target cart to Slot-2.
That means, insert a GBA cart in slot 2. Press A for OK so the tool can read your GBA cart. It shall take a few seconds.
In the TOP screen you can see in a little blue box:
Slot-1 Card [name of your flashcard here]
Save File Size: Auto [could be different for you but ok]
Rom Backup Size: Auto [could be different for you but ok]
It shall show you a set of sav files under the blue box if you have sav files in the folder named "GBA_Backup" in your MicroSD Card. If it's empty, then in the grey part you won't see any file and that's totally OK.
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In the BOTTOM screen you will read:
GBA Backup Tool
<ROM Information>
Game title [title is like in abreviation]
ROM Size: could be like 16MB, 32MB, 8MB, 4MB [depends of the game you have in slot 2]
SAVE Type: FLASH 1M(128KByte) <--- so far I know, the GBA Pokemon games are that.
You will see a little blue box saying: [ Save Backup ]
That's what you need to look at before taking any actions, so you know what you're doing. Shortly, this is the first menuscreen for you.
You can read below it:
(A) Specified SAV file is updated. (if you press A on the selected SAV file on your MiscroSD Card if you have any SAV file in the GBA_Backup folder, you can update the existing SAV file then on your MicroSD.)
(B) New SAV File create. (this is what you start with, this means you create a copy of your SAV file and place it automatically in the GBA_Backup folder, this does not mean to delete your current SAV file on the GBA Cart and make new one. Each time you press this and accept, it will make multiple copies, file ending in the number you have of the SAV file.)
(X) Change ROM. (press X, it will prompt you to take out the current cartridge and insert a different one so you can make a copy of the SAV file, press A after to let the Tool load the new cartridge's data.)
® Change Command Mode. (By pressing shoulder R, you go to a different menu screen which is from SAVE Backup to SAVE Restore.
So, if you press R once, you go to [save Restore]:
In this menu screen you can select a copy of a SAV file from your MicroSD Card's GBA_Backup folder and place it back in your GBA Cartridge. This is a restore. You would do this if you modified your SAV file in computer or in another GBA Cartridge, for example, if you have 2 of the same GBA Cartridges like, two Pokemon Emerald.
So, let's go on the options, they are:
(A) Restore data in Card from SAV file. (this means, you are going to place a SAV file from your MicroSD Card in to your GBA Cartridge in Slot-2. It will overwrite the existing SAV file in your GBA Cartridge and you can't get it back. So, before using this feature, make sure to get a copy first of your existing SAV file. Never place a different SAV file like from a different game on another game. You can place FireRed on LeafGreen and visa versa, or Ruby on Sapphire and visa versa. Do not place Ru in Emerald or Sapphire on Emerald or visa versa because your game will crash.
(B) SAVE area of ROM is initialized. (this means, delete existing SAV file on your GBA Cartridge. Be careful with this because you will loose your SAV file forever.)
(X) Change ROM (to switch GBA Cartridge and load data of a different cartridge)
(L)/® Chaneg Command Mode. (By pressing L you go back to the SAVE Restore feature. By pressing R you go to ROM Backup)
So, now we are in the menuscreen of: [ROM Backup]
Here we can extract a copy of our GBA Cartridge's ROM. We can then play the ROM on an emulator. You might want to also copy the SAV file in order to continue your game on a computer using an emulator like Visualboy Advance. So, the options here are:
(A) Specified GBA File is updated. (in case you already placed a copy of your GBA ROM in the GBA_Backiup folder, you can see the titles in the TOP screen and overwrite the existing copy with a new one from your original GBA Cartridge. You cannot insert/overwrite/modify existing ROM on your real/original GBA Cartridge.
(B) New GBA file create. (Here you extract your GBA Cartridge's ROM and place a copy on your MicroSD Card in the GBA_Backup folder.)
(X) Change ROM. (You can switch GBA Cartridge here with another one you want to extract the ROM of.
(L) Change Command Mode. (Brings you back to the SAVE Restore menuscreen)
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What you must know:
-Always make a backup first of your SAV file atleast more than one time.
-You cannot insert a new ROM or modified ROM in your real GBA Cartridge.
-You can only insert a new/modified/same SAV file on your real GBA Cartridge.
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Why you would want to use the GBA Backup Tool:
-So you can play multiple SAV files on one game, but you must backup the SAV file again and restore the other one, and so on each time you want to play a different one.
-You could do international trades by sharing SAV files and then restore the SAV file back in your REAL GBA Cartridge.
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What you must set in VisualBoy Advance before saving/overwriting existing SAV file you extracted from your REAL GBA Cartridge.
-You must set the SAVE type to Automatic and Flash 128K:
Click on Options, Emulator, Save Type: Flash 128K.
Why? This way you ensure that your SAV file is kept in 128K, by default, VBA saves the games in Flash 64K which will cause no readable data if you restore that in your real GBA Cartridge.
-For Colosseum Bonus Disc: Get infinite Jirachi on your same saved game, but first, get one Jirachi, trade it to another GBA Pokemon game, then reload your SAV file which was saved before you got Jirachi, restore that save file in your GBA and get another Jirachi. As you might know, Jirachi Bonus Disc does not count how many Jirachi you have obtained and means you can get a lot of them and could try getting one with good nature and stats. I did so and got myself an awesome Modest Jirachi with 30 Sp.Atk.
VBA = Visualboy Advance.
Please, make sure to read this very well, and note.