Wow, magnificent work! Really impressive you did this with Sketchup.. can you shed some light on your workflow, your used plugins? The model looks massive, to what degree of detail did you model it? When it comes to high poly situations Sketchup seems to fall apart somewhat, how many polys are we talking on this model?
I used S4U component to build the scales in my building. In concept steps , i used curviloft to build the surface, once i got the surface i can reduce soft edge and make structure line. I turned the line into tube by using plugin.
Indeed, once there are high poly, the sketchup will fall apart. So i use component and save the main building as component. I can modify the building by opening the main building model in another sketchup window.
sorry for my poor English, however there are the plugin i used.
JHS Powerbar
S4u component
Skatter ( I used it to skatter grass ,and make them as proxy
Curviloft
SkatchUV
I think you can learn how to use plugin by following "tutorialsup" in youtube. This channel really teach well.
https://www.youtube.com/user/ahmedfraz07
https://www.youtube.com/user/ahmedfraz07