IPhone – How to extract third party application data (mp3 files) from iPhone6 to Windows 10 computer

It depends whether the remaining files you have are from an encrypted backup.

It won't be feasible to read your backup data if you have an encrypted backup with no Info.plist, Status.plist, or Manifest.mbdx files

However, if your backup wasn't encrypted, it will be possible to read that data. You'll find that whilst the filenames are unhelpful (they're SHA-1 hashes of the file's internal path), the file contents easily readable. It's only the filenames that'll be lost.

If you're looking for images, try renaming a bunch of the files to have .JPG extensions, and see whether Windows Explorer or macOS Finder previews them for you.

There are a few approaches for digging into what's there in bulk. You mentioned using iPhone Backup Extractor, and there's a guide on how a use "Bulk Rename Utility" to read backup data when in this situation.

As MacTrast discovered, it's not a bug, Apple is intentionally upgrading older Aperture, iWork and iLife versions (paid, trial, pirated or otherwise).

[However,] it’s no coincidence that Apple’s support site doesn’t have downloads for the new Aperture, iWork, and iLife updates. They aren’t in our Software Update system either – and there’s a good reason for that. With Mavericks, we have changed the way we distribute updates for legacy versions of our apps

So "legally", downloading the trials from another site just to get the free upgrade is still pirating software you're not entitled to. Apple is just taking the stance that:

We like to believe that our users are honest, even if that belief is in vain.

Also, the Aperture trail page does specifically state that you need to uninstall the trial before purchasing it from the Mac App Store.