How to import CAD Models

Hi all.
i have been working with CAD systems in many years, but are new to this fantastic software, i would like to import my CAD models into this to make animations.
I am trying to omport via STL and Wrml, but nothing is loaded.
Does any of you have expiriance with this ?

Best Regards jens

I never experienced problems importing STLs (binary STL, not sure for ASCIIs). What exactly is your issue?

Is it showing up in the Outliner window?
Maybe it’s come in very very large or very very small