To add a custom command to the shortcut menu of the row or column header element, or to the one of the filter panel, use the com.nomagic.magicdraw.dependencymatrix.configuration.DependencyMatrixActionRegistry class.
The com.nomagic.magicdraw.dependencymatrix.configuration.DependencyMatrixAMConfigurator interface has a single method that adds custom commands. The location of a new command depends on the parameters, such as the following: