Best export to Riptide and then C4D

 From:  okapi
OBJ or LWO work great for transferring to C4d, or modo for that matter.
Make sure you use the latest beta.

I see no reason why you would want to import tris or quads into C4d, since C4d supports Ngons?...
Even if you are editing later in c4d, you are better off with a clean Ngon based mesh, in the case of hard models.
I guess the only reason is if you would want to try to do some SubD modeling with the mesh, but you will never get a mesh with flowing loops from
a nurbs modeller, that is just not the point.