This webinar introduces Flowex's molten salt reactor (MSR) modelling capabilities and explains how the software supports advanced nuclear system simulations. It demonstrates how reactor geometry, neutronic behaviour, fluid properties, and thermal-hydraulic calculations are integrated within an axisymmetric reactor model to simulate both steady-state and transient conditions. The presenter also shows how users can build reactor models, configure neutronic feedback, analyze detailed reactor results, and customize calculations through scripting. Finally, the session highlights Flowex's ability to model complete reactor systems, including heat exchangers, steam cycles, control systems, and transient events such as control rod movements.