CPM (Cooperative Problem-Based learning Metamodel) is a visual language for the instructional design of Problem-Based Learning (PBL) situations. This language is a UML profile implemented on top of the Objecteering UML Case tool. In this article, we first present the way we used CPM language to bring about the pedagogical transposition of the planets game learning scenario. Then, we propose some related works conducted to improve CPM usability: on the one hand, we outline a MOF solution and an Eclipse GMF solution instead of the UML profile approach. On the other hand, we propose some explanations about transforming CPM models into LMS compliant data, and tool functionality.