Unmerge merged CC question?

I don't think there is any way to unmerge a file like that. The tutorial you found requires the CC's original package file, and that tutorial is the only thing I've seen about modifying the contents of a merged CC file. If you don't have the original CC to remerge into smaller files then I'd just leave it be. I know Store content is thought to load more reliably if kept in ebc files smaller than 200MB. But I've never seen clear answer to how to size merged package files. I've had merged hair files around 500MB before. I did remerge my CC hair into smaller files a few months ago, but I haven't noticed any difference.

I have no idea if it's possible to split a file like that.