The initial Command Disc which the designer automatically adds to all new craft has an integrated battery fuel tank, and gyro. During flight, however, crucial information about these components is missing, preventing you from transferring battery power from another component or seeing details like power remaining in the battery or consumption of the gyro.
Please fix this by adding the inspectorEnabled="true" attribute to the initial Command Disc's FuelTank and Gyroscope subparts.
Command Discs that are added manually in the designer have that attribute and work as expected. There's no reason the automatic one should be any different and it just causes confusion that feels inconsistent / buggy.
The in-game bug reporter wouldn't let me capture a useful screenshot of this. Here's an annotated screenshot depicting and explaining the problem:
https://i.imgur.com/7nT1Ptu.png