In general, a transform can be driven by a property of the component.
For performance reason it’s better to scale (transform) a whole link instead as a custom joint type.
If it’s a sliding door:
Define the door as a joint and apply IO-Control Wizard for it:
- Extract the geometry as a link
- Define translational joint
- Apply wizard
You can follow this tutorial until to part 6. Instead of EOAT Wizard use the IO-Control Wizard
If it’s a collapsing/telescopic type of door, then it gets more complicated than that…