Yes, you can delete other files, however, my preference is to copy-paste my packed project into my source file folder, and overwrite the existing.
What that does is combine my packed project materials along with any media files I did not use.
This is important to know...packed projects do not copy files from the library, only the ones actually used in the timelines.
I'm looking for a PDToots tutorial on this, but it eludes me.
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