There is a known issue with Acrobat and 3D models with texture maps. The workaround is to create a texture on the model in Studio and then create the 3D pdf file.
1) In the Tools tab, click on Texture Maps>Generate Texture Maps and click Apply.
2) From the Application button>Create 3D PDF.
The 3D image will now keep the texture if the model is clicked in the Acrobat PDF.
To remove the texture from the model, go to the Tools tab, click on Texture Maps>Convert Texture to Vertex Color.