During the Unified Challenge (UC) 15 simulation experiment, we faced a requirement for a persistent chemical event to stimulate Commanders and Staffs at multiple echelons (Brigade-Corps). This was used to improve the representation of Maneuver Support equities. We found that none of the simulations available to the Community of Practice (CoP) had the ability to model persistent chemicals and effects within the Training and Doctrine Command (TRADOC) Battle Lab Collaborative Simulation Environment (BLCSE), and our current resource-constrained environment made development of a new simulation unfeasible. Therefore our team began looking at simulation software re-use to enable the CoP to modify current simulation software that would provide the required capability. This paper describes the development process and the simulation design patterns used to provide lessons learned, which can be shared across the CoP, in order to enhance other simulation software re-use activities.