When you edit a custom rule and corresponding analysis module, the changes apply to all projects.

Before you edit a VI, .NET assembly, or DLL analysis module, you must unload the analysis module from memory. You can unload all analysis modules by right-clicking anywhere on the Analysis Modules tab of the Configure Sequence Analyzer Available Rules dialog box and selecting Unload All Modules from the context menu. In the TestStand Sequence Editor, you can also select File»Unload All Modules to unload all modules, including analysis modules, from memory.