It's a False Positive for a Trojan. Turn your AntiVirus software OFF and download the installer. Turn the AV back on once the installer download is completed.

Here is how I do it:
1. I turn my email progam (Outlook) OFF, and I only have the download page for the product installer open in my web browser (so that nothing else is accessing the internet while my Anti Virus software is OFF).
2. I download the file and take note of where I saved it on my computer.
3. I turnt my AV software back ON*, then add the downloaded installer to my AV's exclusion list.
4. Install the Captain Sim product.

* Sometimes the AV will immedialy move the installer file to its Virus Chest/Vault when you turn the AV back ON. Just restore it from the vault and add it to the AV's exclusion list.