Thank you for mentioning this resource.
Btw I really think that the world's obsession with learning to hear intervals before hearing harmony qualities (minor triad, major triad, dominant seventh, diminished), and before hearing harmonies within a key (I or i, V, pre-dominants, VI or vi, V/V) is a wrong order to master things. I still can't solidly tell apart a minor sixth from a major sixth, but so what? The more important skill to me is to focus on a chord that currently sounds, so that I can interact with the real tonal language (homophony) of the last 2.5 centuries. This way I can eg. play by ear the melodies with chords that stuck in my head (including from way in the past).
We switched from polyphony and intervals on top of each other to chord progressions around Bach's time, and since then intervals aren't the main thing, I'd say.