I use winrar.
You select files: bootskin.ini , Your picture boot.bmp (4bit), Progressbar.bmp(4bit)
This 3 files only.(jafo
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)
and right click unzip with winrar select .zip (and not.rar) and you change the name of the archive like that:
"my boot.zip" to "my boot.bootskin"
very simply.
And if you want to included permissions select the "my boot.bootskin" and "permission.txt" and unzip (allways in .zip file and not in .rar)
hope that's help