NO Optional arguments are for compiler not the package:
You need to use InstallCommand:
///<summary>/// Gets or sets the optional arguments for the bootstrapper compiler.///</summary>publicstring OptionalArguments{ set; get; }
///<summary>/// The command-line arguments provided to the ExePackage during install. If this attribute /// is absent the executable will be launched with no command-line arguments///</summary>publicstring InstallCommand;