CreoIllustrate_64.exe is a self-extracting archive that extracts the required files for the setup of Creo Illustrate to a temporary directory and then runs Setup.exe. Note that all files contained inside of the self-extracting archive are directly accessible from the media downloaded from PTC.com. The self-extracting archive is only provided as a convenience for the administrators who need it available as a download. CreoSetup.exe is a wrapper application for chaining the installations of several installers in the archive, including CreoIllustrate_64.msi. Running the MSI file alone does not constitute a complete installation of Creo Illustrate. However, you can customize the installer in these ways:

Use 7-Zip to extract the archive to a folder, and then modify its contents. Continue to Creating and Deploying a Customized Installer for an example.