I'm looking at the bonus tracks on this box. I think there is a mistake. There are supposedly three versions of Between The Worlds: LP c. 3.17, Single c. 3.19 and Alternative Single, c. 3.30 but we actually get a fourth version, though it's all a bit mixed up.
CD1 has the LP and single versions and they are clearly different. All good.
CD2 adds an alternative single version which is a bit longer. But what it calls the single version is not the same as on CD1. It's similar to the LP but a little longer (3.39).
The DVD has this rogue Single Version but not the Alternate Single Version. It's a shame because the original single version on CD1 is more significantly different - it's a different recording rather than just being a remix - so that would have been a nicer one to have in 5.1. I imagine they do still have the multi-tracks because it's on the same tape as Lights and Music In Dreamland - all recorded at Phonogram studios, as pictured in the book.
So, we've ended up with two slightly different mixes on CD2, one of them in 5.1, but are missing out on a more significantly different recording, though the 'proper' single version is still fairly similar, so it's not a great loss. I'm happy that we got a B side in 5.1 (Lights).
(The two longer mixes are very similar to each other and to the LP version, I think. The alternate single version has some guitar removed from the intro so that it's more piano-based and is not as 'bright'. Both mixes have a longer intro and the bit around 2:30 to 2:45 is a bit longer.)