1. I can think of 3 possible things to do:
a) You Morph will have a Building Material assigned. Modify the Transparency setting of the Surface specified for the Building Material to change the transparency of the Morph.
b) If you do not want to change the setting of the Building Material's Surface, you can also apply a Graphic Override to the 3D which would override the Surface of the Morph with a transparent Surface. The advantage of this would be that you could save 2 Views, one with the Graphic Override applied, and one with not applied, so the Morph will be displayed transparently as needed.
c) Set the Layer of the Morph to Wireframe, which will make the Morph completely transparent.
2. If you convert the imported SketchUp geometry to a Morph, you can then make the individual edges of the Morph hidden as needed.
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