You can install both Standalone and Plug-In versions, but not at once. Please select either the Standalone or the Plug-In version and install it, then rerun the setup and install the other version.

• installing Standalone version
• installing Plug-In version (for Photoshop users)
• installing Plug-In version (for Photoshop Elements users)
• installing Plug-In version (for Paint Shop Pro users)
• installing Plug-In version (for other graphic application users)