Hi @JdB! Good shouts!
Q1: nice bug find. It’s logged and will be done this sprint: Viewer: support boxes · Issue #270 · specklesystems/speckle-server · GitHub
Q1a: the image in gh: it might be something because boxes are gh native objects somehow, and our converter doesn’t know what to do with them. I think @AlanRynne is the most legit authority on the matter though 
Q2: logged and ticked off apparently here: Feat Revit: Additional conversions · Issue #394 · specklesystems/speckle-sharp · GitHub. Perhaps @teocomi and/or @Ollie can provide more info on the status.
Q3: Also logged in Feat Revit: Additional conversions · Issue #394 · specklesystems/speckle-sharp · GitHub, and discussed Sending Walls and Rooms from Revit 2020 to 2019 - #5 by a.halim - not sure of the status - again dropping that hot potato in the hands of @teocomi 