Software from Lucrece (motofan.ru), which is very useful for extracting the iconres.ezx file. The usage only looks complicated, but it is not that much if you read it carefully

Extracting the image files
1. UnRAR the archive and run the program
Extracting from iconres.ezx and converting g/k files to editable image files
2. Go to File-> Open EZX, browse to the iconres.ezx file, and hit Open
3. Create a temporary folder for the g/k files, select it and hit Open again
This will extract all g/k files in that folder
4. Go to File-> Convert All
5. Select any file from the temporary folder and hit open
6. Create another temporary folder for the image files, select it and hit Open again
This will convert all g/k files to .bmp, .png and .gif files

Converting the image files back to g/k files and iconres.ezx
1. Go to File-> Convert All
2. Select any file from the temporary images folder and hit open
3. Create a temporary folder for the g/k files, select it and hit Open again
This will convert all image files to g/k files
4. Go to File ->Save EZX
5. Open the folder from 4. and hit Open
6. Type in iconres as a filename in the next menu and hit Save

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