<DIV>1) You can sketch the curve either in the assembly or in a part or sub-assembly. I prefer creating a skeleton model (Component > Create > Skeleton) and sketching my curves there.</DIV>
<DIV>2) Yes, but why would you want to do that? I would be cautious.</DIV>
<DIV>3) Yes. Define it the same way you would a regular EFX assembly. You can define any assembly as an EFX assembly.</DIV>
you can use the EFX screw functionality in any assembly. You only need to define the project. I assume that you start pretty new with EFX. There is EFX 4.0 available since a few days which has a completly new screw functionality which is much better thant in 3.1. It has a great new dynamic user interface for configuring the screw connection. It isalso able to work with already existing components for screws, nuts, washers etc (with small customization work).
If you want more information about this send me an E-mail to [email protected] (I am one of the developers of EFX).