Exporting Terminal Log
To export the terminal in MatterControl you need to first enable the Terminal menu, as shown below.
Short Video showing the Exporting Terminal Log
You will then have the option on the right side of your screen for the Terminal. Go into this menu and find the "Export" button at the bottom and use this to export the log.txt file to your desktop.
WARNING: The Terminal Log will only last for 15 minutes of history so be sure to capture the log within a few minutes of the error happening.