The discrepancy between students' understanding of domain knowledge and their actual competencies to use tacit knowledge for a given task has been an issue to consider when instruction is designed, implemented, and revised. In this study, the researcher examines teaching and learning processes in which a Problem-Based Learning (PBL) design model was crafted and used for an advanced instructional design course in the educational technology field. The focus is on the researcher's ongoing and recursive reflective experiences in reviewing design components of the model, analyzing the motivators and difficulties students faced, and offering alternative methods to improve the initial design. The findings show that the PBL approach played an instrumental role in creating real challenges that the target professionals may experience. On the other hand, observed difficulties in PBL include intrinsic and extrinsic cognitive loads associated with the complexity of the instructional design process, self-regulated learning skills, learning beliefs, and supporting strategies used for team dynamics. The patterns identified in the behaviors and perceptions of effective and struggling students are interpreted. Based on the findings, new constructs of the model were suggested for further improvement.