Platforms, roofs, walls and so on are generally implemented as splines which can be attached to helper points on the station components themselves.
Track and platform spacing of multiple track stations are suitable for UK installations. Single track and island variants will suit any national standards.
Most of the stations now use a custom written library which reimplements most of Auran's script. The principal advantages are that the fixed track sections of the platforms are short (allowing the stations to adapt to curved track layouts) and the individual platforms can be renumbered and grouped (allowing combinations of objects to be configured to act as if they were one object)