You can check for interference of parts with 'analyze Interference' on the Inspect Tab. By selecting two group of parts you can find out if the touch each other. But that's no giving you an alarm when you change something and after that 2 parts touching each other. An other option is to use the Activate Contact Solver on the same Inspect Tab. First Right click on 2 parts in the model-browser and add them to the Contact Set. Now Activate Contact Solver and drag under constrained parts and when the contact the moving stops. Is that what you mean.