Weirdly although I knew the other version worked best, I did this reverse order first. Reflects the topsy turvy nature of this album and my life, really. But also because I had already done 'Better Songbird' I had the acapella warped already, so it made sense to do this first. As it turns out, the other worked best and I knew that....but I wanted to play with the Madonna vocal and instrumental.
Sadly although the acapella worked well, the RX8 extraction of the ABBA track didn't - as I said, not many ABBA parts and no instrumentals bar the ones on the albums. And the poor music box synths got rather crunched by the AI, so that was a no-go.
But I suddenly remembered that Madonna has covered this song with William Orbit and never released it - the acapella and instrumental leaked online many years ago. So I did have a cover instrumental of Angel, and a Madonna acapella. Not sure what she did with the tuning, but the vocal doesn't work over Songbird, but the Songbird vocal does work pretty well over the instrumental - with a few Mads interludes, courtesy of the acapella, remaking the original track that I couldn't find in decent quality anyway.
I quite like the Orbit version - she released an orchestral version of this on an Xmas album, without the drums or synths. Shame, given the original's electronic feel, I think that worked better, rather trip-hoppy.
Madonna - Like An Angel Passing Through My Room (ABBA)
Fleetwood Mac - Songbird