1) I create a LayoutGrid and set its background colour to 'black' (to match the background colour of its page)
2) I subdivide the LayoutGrid into 2 sections (9-3)
3) I select each subdivision and set its background to 'solid' and its colour to a shade of blue (via its 'style' dialog)
4) WB18 subsequently displays the LayoutGrid with 2 subdivisions each having a blue background as shown below:

5) However, when previewed in a browser, subdivisions which contain no objects (or whose objects are smaller than their neighbours') have a black background, as shown below:

Is this an error on my part or an issue with the software?
As an aside: it would be nice if 'subdivisions' inherited the background (etc.) settings from the right-most existing section - this would save having to change each one individually after they have been added, as the 1st would be automatically copied to the 2nd upon its creation, which would then be copied to the 3rd etc...