The lossless soundtrack available under Baldur's Gate 3 extra, results in a 600~MB download, rather than the 2.7gb anticipated by the GoG launcher itself. The archive is corrupt.

Can anyone recreate this? The .mp3 version downloads and extracts just fine.

Had the same issue, although galaxy said it should be 1.* GB I think. Didn't try the mp3. Didn't bother raising a support ticket yet, as I expect fixing this would be low priority versus any other launch period issues.