Presented here is a blocking trap case. White's pawn has been isolated at <BD>d1</BD> from the rest of its pieces. Unless black moves the pawn at <BD>d2</BD> or at <BD>d3</BD>, the only way for white to get away is to circumvent around the blockade and thereby lose many important moves.
Keep pressing <BD>Forward</BD> in the <BD>List moves</BD> window and observe the turn of events.