Random thought I just had:

If the GMs won't take action for whatever reason, then I wonder if submitting it as a bug report would at least get those furnishings removed. Members of the FC that own the plot below should not be able to place the items on the plot above that they do not own.

Same with the items blocking the pathway. The anchor points for the furnishings appear to be placed outside of the plot's boundaries. Players should not be able to place items outside of their plots.