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.
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