After running out of Main Range audios to borrow, I decided to move to The Lost Stories, starting at the beginning with the Sixth Doctor "lost season" and The Nightmare Fair. I still have the novelization of this one, so I was curious to hear it. And after listening to the first episode, I realized I should've reread the novel first, so I'd be less confused about the settings and events. Since this was not conceived for audio, I don't think it conveyed the visual aspects all that well, even with the revisions they made.
So anyway, I stopped after the first episode and read the whole book, and then I followed along in the book as I listened to the second half. It was interesting to compare them, the way the audio put in dialogue to illustrate actions the novel narrated, and the way it left out some elements that were mostly visual, like the third alien prisoner. I still think it would've been much harder to follow without the novel descriptions to remind me what was going on, though.
As for the story, I remember liking it back in the day -- at least, it's the only one of the three novels from the "missing season" that I found worth keeping. But on revisiting it, I find it rather unfocused and lacking coherence. The thread about Kevin's abducted brother and why he was abducted is barely addressed in the novel, and though the audio clears it up slightly, it's still slapdash. There were a couple of throwaway references to some sort of spacetime vortex connected to the Toymaker, but they were referenced in passing and then forgotten and never connected to anything. The alien prisoners are weird additions, and there's that whole shaggy-dog digression about the cyborg soldier's endless war and how it poses a threat to Earth and then it's just forgotten altogether, and the cyborg doesn't serve any real purpose beyond providing parts for the Mechanic alien. (In the audio, Colin Baker mispronounces the Mechanic's species name, Ventusan, as "Venusian," or else the scripter misread it.) It was all just a bunch of pieces carelessly tossed together. It feels like a rough draft that would've been polished before being filmed, but for some reason Williams didn't bother to polish it when he novelized it, and the audio is way too faithful to its flaws.
As for the Celestial Toymaker's Great Work being just a killer video game... well, maybe that came off as cutting-edge back in the early '80s, but it seems a hell of an anticlimax today. And it's an even duller climax in audio, where we can't even see the game being played, just hear the bleeps.