A fundamental building block of digitalisation is the digital twin, a virtual duplicate of an entity that is accessible to relevant internal and external stakeholders and updated throughout the system's lifecycle to help decision-making associated with development, adaptability, production, and service. This chapter examines the application of the digital twin to achieve more effective development of a plywood panel repair line, a machine system featuring precision dynamics and mechanical complexity, by enabling better cooperation among the multidisciplinary engineering team and other stakeholders. For this case example, a digital twin was developed for the system's most critical elements: the vacuum conveyor, the defect detection system, and the repair area. Well-timed communication among members of the product team is essential to achieving rapid design iteration for complex systems such as these. Realising the example revealed challenges with respect to coordination, complexity, and interconnectedness, and the management of data and software intensiveness that were addressed via digital twin data management, the use of surrogate models, and virtual prototyping. Results suggest that cooperative development within a digital twin business ecosystem enables more informal controls that promote initiative and creativity from development personnel and leads to faster and more effective product development. When the simulation methodology allowed correct automation codes running already in the testing phase, user interfaces, digital service data collection, and reporting could be done in advance, facilitating on-time feedback on the development. Thus, the proposed approach will fasten the supply time significantly.