UART from SCuM can pass through the nRF serial connection, but there are still minor problems that need to be fixed in the setup. For now, it’s easiest to use a USB UART device. The one found here works well. Any serial device must be configured to 1.8V to properly work with SCuM. You can use any serial monitor (set to 19200 baud), such as the one built into the Arduino IDE.