Isle of the Kakapo (http://www.isleofthekakapo.com/) has released RailModeller Pro 5.1, an update to their model railroad and slot car layout design solution for Mac OS X.
RailModeller Pro offers design tools that enable hobbyists to design model train and slot car track layouts via drag and drop. The app includes a library catalog covering over 200 track systems in all major model scales, allowing for custom designs of almost any layout a user can visualize.
Version 5.1 adds native support for tunnel sections, including the automatic creation of tunnel portals between plain and tunnel tracks. This is designed to make it easy to distinguish visible track sections from tracks running underground. The update also adds Layer-Defaults that optionally provide default values for elements newly inserted into a layer.
RailModeller Pro 5.1 is available for $39.99 exclusively through the Mac App Store in the Graphics and Design category. A free version, RailModeller Express, which is suitable for small layouts with a limited number of tracks and layout dimensions of up to 0.5km – is also available through the Mac App Store in the Graphics and Design category.