I think the resistance shown by Kelly, as well as the cardboard mockup of the windows they built to convince him in the TV series, was dramatic license.
More 'let's help the viewers see it' than helping Kelly see it. Kelly was an engineer. I'm reasonably sure he'd have seen the plans and understood without the need for a full-size mockup. It makes for a much more engaging moment in a TV drama, though, so it's a bit of dramatic licence I can get behind.

The episode on Spider was my 2nd favorite, after the episode on Apollo 12.
They're in my top 3. Apollo One is my favourite, for very different reasons.
The series could have discarded the episodes on Apollo 11 and 13 and been the better for it in my opinion.
I'm not sure a series about the journey from the Earth to the Moon could have got away with not having an episode about Apollo 11. The difficulty is that it's inevitably the episode that tells a story the viewers most likely to tune in are already very familiar with. The Apollo 13 episode is probably my least favourite, but of course they had not long made an entire movie about it so had to find a new angle on the story. I think it's a shame that Apollo 16 was relegated to little more than a footnote in the astronauts' wives episode. Maybe Apollo 13 would have suited that better, or maybe they just couldn't find enough new to talk about with Apollo 16.
Overall, though, a damn good series with some amazing moments.