My typical work flow is to make a model in Trimble sketchup. (easy to learn), then export collada file from Sketchup and import it into Blender. Then export .obj from Blender and use that in Tg.
If you pay for full version Sketchup, then you are allowed to export .obj files directly.
Question: Can one export cameras from Blender to use in TG?
R.