To enable expert robot configuration, you would just simply click on the name of the file, then check the expert robot config box. But, that would allow you to manually edit robot-config.cpp, not bring up the graphical user interface for the robot-config. Try restarting the application.
I’m so sorry for my incompetence, but what do you mean by selecting the name of the file? do you mean in file explorer, the top bar on vexcode? I’m not quite sure ;___;
You’ve probably already figured this out, but the bar at the top.