I'm having an issue importing parts that have threads on them using the coil feature in Inventor. The radius totally messed up as shown in images #42 & #43 (this was exported as a .stp file, the .iam and .ipt files have the same issue). I exported as an .obj file and the result can be seen in image #40 - not even close...
I've attached the .ipt file used in these examples.
I forgot to mention, I am using KeyShot Version 7.3.40