Hi Mike,
I have modo version 9 and played around a bit with importing multiple textures from modo into RC. As far as I can tell the best way to do this is to use the 0 to 1 UV space. The way to have multiple textures utilize this space is to use multiple materials, each with a texture. I have attached a modified model of my shed front that I made six blank textures for in Photoshop. In modo I created six materials and assigned one of the textures to each of the materials. I then selected different elements of the shed and assigned different materials to them. When I imported the model into RC all six textures were there.
Here is an image showing the six textures I made in Photoshop.
Here is an image showing the six textures exported from RC after texturing.
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This image indicates the Tile type that exports multiple textures that utilize the 0 to 1 UV space.
Here is a link to the .obj file I modified in modo along with the 6 textures. It also includes a folder named test that contains the model and textures exported from RC after it was textured. If you download the RC project from one of my previous post, you can import modo.obj and texture it to see how it works.
http://www.digital-mapping.net/forums/CapturingReality/2018/modo.zip
Here’s a link to the model on Sketchfab: https://skfb.ly/6wyxV
You can use the Model Inspector on Sketchfab to checkout the wireframe, textures, and UV’s.