Unfortunately, it is not possible to install multiple versions of Sapphire for the same host on one system. Our Sapphire Installer is designed to replace all other versions of Sapphire for your chosen host (but not for other host products). This prevents confusion from multiple copies of the same effects, and allows your saved projects to automatically use the new version. To use an older version of Sapphire on your machine, please uninstall the current version and install the older version.