I don't think you can go get individual RealTracks via your account, but you can get the 'Sets' via a download link in your account. I assume this is different than the 'Paks' you mention.

Log back into your account at the main store (separate from the forums) and check your purchases.
I'd be surprised if this aspect was different on a Mac, I would think the 'Sets' still come with an installer that lets you re-install that set.
In image below, the list goes on well beyond the bottom of the image, listing all the RT Sets I have access to.
Plus it lists my downloads from last year, so any BonusTracks or Bonus material available last year and not this year is still available should I have any issues like you mention.

If by Paks, you meant Sets, this post is completely useless.. I think of Paks as the whole package, like the UltraPak ..
As you can see I don't have to download the entire UltraPak, but can get down to the RT Sets level.

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Last edited by rharv; 06/09/18 06:42 AM.
Make your sound your own!
.. I do not work here, but the benefits are still awesome