Unable to insert any constraints in importet Parts

Hey there,

i importet a .stp-file into the 3Dexperience-Environment via the import-function of the system. Now I want to use Joints and Forces in order to build up a mechanism. I was trying to use the "Mechanical Systems Design"-App, but i wasnt able to insert any Constraints.

Is there a way I can use the existing data, or do i need to rebuild it by hand myself?

i am using the full academia-version of 3dexperince R2018x

thank you in advance

Malte Bethke