Also "Quantum Space" was stupid and unnecessary, presenting a ton of new issues, complications and opportunities for the universe and yet treated as an offhand light hearted kind of joke.
The gag with the reporter was always in the script but the inclusion of Quantum space appears to have been a late addition – maybe to make it easier for the viewer to understand why she puked.
But like you said, it does knock continuity a bit with it just being slipped into the script.
http://themadgoner.com/B5/B5Scrolls/B5Scrolls.htm#Screen1_14_4I remember the original version of the script didn't have Quantum space. It was simply Hyperspace. The gag with the reporter was the same though, except her nausea was caused by sitting in the "God room" while the jump point was forming. The idea being that most people would be unable to handle seeing, and feeling, space being warped so closely in front of them - usually they'd be in the bowels of the ship I suppose. She didn't have her "space legs", as it were. I'm not sure why it was changed, but personally I prefer the original version.
Quantum space was described as "Hyperspace, but blue". Paul Hegg came up with the look of it eventually, using animated displacements and a few layered procedural textures. We wanted to add some moving volumetric stuff into that one shot, which the ship would be seen flying through, but there wasn't enough time.