This article describes the iterative design, development, and evaluation of a case-based learning environment focusing on an ill-structured sales management problem. We discuss our processes and situate them within the broader framework of educational design research. The learning environment evolved over the course of three design phases. A semisummative evaluation of student concept maps after the third phase revealed unsatisfactory learning outcomes. This paper focuses on how we investigated design flaws that contributed to poor learning performance. A specific focus of our investigation was the use of Google Analytics data, which uncovered weaknesses in our design. Based on our findings, we used a rapid prototyping process to redesign the learning environment, emphasizing interactive and multimedia-rich elements. Processes and methods are reported along with discussion of implications for case-based reasoning, including relevant design principles. This article will provide insights into resolving design tensions for researchers and practitioners seeking to advance theory and practice in similar domains.