My understanding is that his parents were first cousins. Where I got that idea I'm not sure, but it is worth checking on. His father was Edwin Abbott, and his son was too, so the progression is interrupted. By the way A Square = (Abbott Abbott) = A^2 ).
2) Is the University of Wentbridge a reference to a real Spaceland institution?
It is a pun on Cambridge, Abbott's home University. But there is a Wentbridge half way between London and York, although there is no university there as far as I know.
3) In the chapter on painting, the Square says that women have only one side. Don't they have two - a left and a right side, as it were?
True. That would give some interesting possibilities for distinguishing orientations, although that would be superfluous since the eye is always distinguishable from the posterior (I believe).
4) How was Flatland received when it was first published?
Mixed reviews. We should look at them in some folder sooner or later.