In this paper we describe the design and development of a \textit{route training system} for individuals with cognitive impairments (CI) living in residential care facilities. Learning to move autonomously in public spaces is a fundamental skill for people with CI, who face several challenges to independently and safely move around. Yet, exploring opportunities for route training support, especially in residential settings, has received very little attention. To explore these opportunities, we followed a design and development process based on inclusive design practices that considered the organisational context and aimed at involving people with CI in the software design. To ensure our solution addressed the identified needs and abilities of this heterogeneous population, we further framed the route training definition as a \textit{design process} that is enacted by the system, making the trainer and user co-creators of a personalised training. In this paper we report on the needs and challenges for mobility training in residential settings, introduce the design and formative evaluation of the route training system, to conclude with reflections and considerations on our methodological approach.