Don't think this has been posted yet, so please disregard if it has. ^^
The "corrupt file" problem is, I think, pretty simple to fix and prevent. When you
create a bootscreen, don't put the needed files in other folders within the zip file. The needed files (the .bmp and so on) need to be in the
top level of the zip/bootskin file!! This has worked for me on the six or seven skins I tried.
If you are
downloading a bootscreen and get this problem, simply rename the folder to a .zip file, then extract the files as people have posted before. Creating a one-leveled folder with only the needed files in it is what you need to do.
I hope this helps!!
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