The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries.
From ACTi Corporation:
Project Design, Anytime, Anywhere!ACTi ProjectGo! is a project design app for ACTi IP surveillance system. Easy to find ACTi cameras and lens fulfill your requirements. Also, bandwidth calculator gives you the idea how much bandwidth is required in a project easily.
