I'm confused about downloading this program. Can you explain to me steps of downloading this program?
The Icarus is bundled with the main application called AspenOne. You can find more information using the official website from where you can download a trial version as well.
Official website: http://www.aspentech.com/products/aspen-icarus-process-evaluator.aspx
Note: You might need to register in order to properly download and have access to the software.