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1. Fixing Non-Manifold Geometry
Preface:Anchor preface preface
It is easy to become distracted by new toolkits/workflows or competing software. This guide will briefly go over the most important requirements for prepping your model for a game engine
1. Fixing Non-Manifold Geometry:Anchor fixgeo fixgeo
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Unreal Engine warning if this model is exported as is: 
3. Fixing Overlapping UVs Anchor fixuv fixuv
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The lowest polygon tessellation will do. If the model has curved surfaces, this setting would need to be tweaked. Depending on the modeling operation Rhino may create too many polygons from a curved surface for a the game engine to handle well.
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- File->Import FBX
- Select objects (important! right-click selects in Blender!) and Ctrl+J to join them
- Move cursor to top right of "3D view" panel. Cursor will become cross-hair. Left-click and drag to split "3D view" into 2 "3D view" panels. Change right panel to "UV/Image Editor"
- Select now joined objects in "3D view" and hit TAB to enter edit mode
- Move cursor to "UV/Image Editor" and hit "A" to select all UVs. (important! you should have UVs already from Rhino)
- Select "UVs" then "Pack Islands" in the "UV/Image Editor" panel. Use .05 as margin.
- Move cursor back to "3D view" panel and hit TAB to go back to object mode. Right click select your model if not selected and export as .FBX. Make sure "selected objects" option is ticked.
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