Some questions & possible solutions:
1. Have you previously installed the GoldCoin wallet on your MacBook Pro? If so, I suggest saving your wallet, then wiping all of the original files to start over again.
2. Is it possible to update to macOS 10.2 Sierra? Perhaps there are some missing libraries and files that you may need.
3. Do you have any other possible computers or smart phones to install the GoldCoin wallet on? If so, then recommend trying them out.
Let me know if this helps; otherwise I can keep trying
