A little item which has more than just decorative use, as the short step is very useful for lining up the Bay Window units. It's double sided, and the half with the flagstones on can be used as a grid guide for matching up the bay positions.
Before putting the Front Gardens in, slide the step into the front of the main unit so that the plain stone end is completely hidden. You can centre the step up by using the centre post of the Long Porch as a jig - the centre line on the step is easy to see. Now discard the Long Porch and introduce the two bays: their fronts line up just in front of the step, and you can use the squares of the flags to check they're near symmetrical. Confused? Then have a look at the 'Buildingz frae Scotland' thread in the Freeware Announcements section of the Trainz Discussion Forum, where you'll find a couple of pictures to help.
(I've used one of those pictures as the screenshot here: you can see the FPSS twice: once in front of the building and again already in position, with just the flagstone part jutting out.)