Software inspections are recommended for improving the quality of software artifacts, but their effectiveness heavily depends on properly training inspectors and other stakeholders in the inspection process. We previously proposed InspectorX, a serious game for learning and training on software inspections, whose design accounts for an optimized cognitive load by offering different levels of difficulty. The game has already been evaluated regarding its learning potential in the detection of defects, revealing positive outcomes. Since then, InspectorX has extended its coverage to other stages of the inspection process, for a more realistic simulation. This paper presents the game's novel features and a new experiment that evaluates them with a bigger sample. Results indicate that there was considerable knowledge retention with just 20 minutes of gameplay. Suggestions on its design made by the experiment volunteers are also discussed.