I have been converting sketchup 8 files using 3dsMax 2010 for some time now, and with certain techniques this can be a quite easy way to get models into Railworks. 3dsMax 2013 does not accept the Kuju plugins, or at least they don't work there. RSC has said that they won't update the plugins for 2013 till they need them at RSC, which they don't right now. You can input sketchup files into 2013 directly, but you can't apply the proper shaders.
3dsMax 2010 does not accept sketchup files directly, but, you can export sketchup files as an Object file using a popular, free, sketchup plugin called "OBJexporter", which you can find by googling it. You then import the .obj file into 3dsMax 2010 and you will have a fully UVW mapped object and a set of texture materials ready to convert to ace files using RSC's RWacetool. Using this technique, you only use 3dsMax for the conversion of the sketchup textures to ace files and the application of the shaders. You can export from 3dsMax2010 using the Kuju plugin that lets you export as an .igs file, which is useable in the RW Asset Editor, which creates the blueprint and installation of your object into Railworks. You don't need to know or use any of the "building tools" in Max to use this process.
There is obviously a little more detail in the process, and there is a bit of a learning curve but if you have a copy of 3dsMax 2010 its worth the work. I have only created buildings and static vehicles so far, so I know that process gives as good a quality finished object as any other technique, and texturing in Sketchup is enormously easier than in Max, not to mention the ridiculously easy process of building objects.
All the best,
Doug
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