如何在InstallShield 2016专业版（21天试用期）中安装此应用程序期间执行应用程序代码？

I create now Windows installation project (ISM) of my C# WPF Prism MVVM modular application. I use for it InstallShield 2016 Premier (21-days trial). In my C# WPF application I have Properties.Settings.Default flag called IsFirstRunAfterInstallation. The type of this flag is bool. I need that this flag I create now Windows installation project (ISM)