Excessive space requirements for download of 0.2.0h, roughly double the published minimums?

I have Windows set up on a partition of a machine that doubles as a NAS using ZFS for its main disk partitions.

As such, I don't have an excessive amount of free HD space reserved to Windows, because Windows can't see or use the ZFS disks. But I do have space well within the published specs for this game.

The PoE2 specs say 100gb of hard drive space, but this most recent patch 0.2.0h is failing to download and install with over 100gb free when the download started.

I did some obvious things like disabling Windows hibernation, disabling file indexing, getting rid of restore points, enabling C: drive compression, and getting rid of stale AppData files, all of which freed up another 50gb, but the install *still* failed after using 164gb, with the meter in the launcher showing me ~10gb left to go.

I uninstalled and reinstalled from scratch, and the downloader is grabbing 90.06gb in its first pass, and then it starts a second download of about 62gb.

As I'm typing this the attempt to redownload shows 20% complete at 18gb, but 40+ gb have disappeared from my available space as I refresh Windows explorer...

As the meter creeps up it appears to be using exactly double the space it says it's using.

41gb on the meter in the installer, 84gb gone from Windows explorer since the download started.