Workflow simulation is an effective approach to investigate dynamic workflow scheduling strategies and evaluate system performance. In this paper we report on a series of performance tests run on our workflow scheduling and quality measurement system. Traditional calculations for workflow scheduling strategies focus only on machine service duration; however, in some contexts the variation of transport time is a significant scheduling factor. In this paper we augment the scheduling calculations to explicitly consider the transportation durations between the machines. In addition, we introduce scenarios with failures of the transport system, e.g. conveyors, which influence the variation of transport durations and evaluate the robustness of workflow scheduling strategies regarding these variations.