Hopefully not too much duplication with folks' comments above:
Overall design: is this missing a vertical firebrick at the outside corner of the burn tunnel and riser? Seems like this goes right up against the orange brick that makes up the retaining wall. I don't remember this from the Solarium build, but I'm pretty sure the builds that I worked on this fall had white firebrick for the feed tube, burn tunnel, and riser base.
4: I would add a sidebar about making cob, or if there's a good commercial replacement. The previous comment about a bill of materials would resolve this; x lbs clay, y lbs sand, 2 bales straw, stable fill, etc.
4: 1.5 - 2 barrels are required, a half for the manifold and a full barrel for the radiator.
5: I think the vertical lines are a bit out of place, the step labels make it pretty clear to me. I would like a heading on this page - something like "An overview of the build"
19: Another angle on the manifold cuts would be helpful.
19+: I would use "barrel" when talking about materials, but once we make a cut or are talking about it as part of the build, refer to it only as the Manifold or Radiator.
19-20: I would swap these pages. One page dedicated to cutting the manifold and installing the flange, then a second for installing it on the jtube.
22: Highlight the flappy-dos in the top image.