Color changes after regen

Scenario

Part 1 has copied surfaces from a skeleton model, which by default is blue, and they are copied as blue. I change the Part 1 to grey by selecting the "part" option and it becomes grey. The problem is that Part 1 becomes blue again after modifying the skeleton model and regenerating.

Questions

Any ideas for preventing Part 1 from changing back to the skeleton model's color?

Thank you,

Kevin