Hi Rich 
In Carrara you can use “Constraints” in the Motion tab to restrict the motion of an object,.
for example,. A door would only open within specific limits of the hinge and door frame,. and it would only swing open on one axis.
To specify “Where” the door would Hinge, you would move the Hotspot for the object to one edge. (where the hinge would be)
then you would set the Motion tab “constraints” to “Axis” and set the X,Y, Z values as required to Limit the rotation of the door.
The door can only be rotated within the constraints now,. you can’t pick it up and move it somewhere, unless it’s a parented part of another object.
There are multiple Preset types of Constraints in Carrara, and there’s also a custom option.
For your Wing flap, you should use an “Axis” constraint, and adjust the angle to suit.
See pics.