The latest installer can be obtained from http://www.integraxor.com/download.htm. Installing and starting SCADA server requires Administrator Privilege. Please request for Administrator right from system/network admin if installing within company system. However, running browser in remote client will not require such privilege.
Do ensure any installed firewall allows full internet access for IntegraXor during installation. Otherwise IntegraXor which act as web server will not work. Most of the time, modern firewall shall prompt for permission when IntegraXor is launched for the first time.
Also ensure no other installation is on going before installing IntegraXor. For instance, Dot Net Framework or some Windows updates could prevent setup from getting initialized. If it's certain that other previous installation is completed or canceled but IntegraXor cannot proceed, check out Task Manager and end any MSIEXEC.EXE process.
It's not a must to uninstall existing copy for upgrading purpose. However newer installation must be uninstalled when downgrading is performed. And it's pretty common to get false alert from Windows that several application might be sharing the same system library, click "Ignore" to proceed.