OpenCandy is one of our offer partners, but the offers are always optional and can be deselected during the setup. Since an executable is run to download and display the offer screen (the actual offers don’t get downloaded or installed without your permission) it can trigger (false) heuristic alerts in some security products. You can upload the setup to virustotal.com to get an overview, most security products correctly identify the file as safe.
We scan all files before uploading them to our servers.