Supervised Capture the Flag games represent a popular method of practical hands-on training in cybersecurity education. However, as cybersecurity training sessions are process-oriented, tutors have only a limited insight into what trainees are doing and how they deal with the tasks. From their perspective, it is necessary to have situational awareness, enabling them to identify and react to any issues during a training session as soon as they emerge. We propose a tool designed in collaboration with cybersecurity educators. Based on user requirements, we developed the Progress Visualization Tool, which provides educators with timely feedback through the session. More specifically, the tool informs educators of the training progression, helps identify the students who might struggle with their tasks, and reveals overall deviation from the schedule. We validated the tool through formative and summative qualitative in-lab evaluations. The participants appraised the impact on the training workflow and gave further insights regarding the tool. We discuss the insights and recommendations that arose from the evaluations as they could aid the design of future tools for supporting educators, not only of CTFs but also in other domains.