In order confirmation e-mail press on the Download link to save the setup file onto your computer. Then this file will begin to download into the default folder location (for Windows computers this is user's Download folder and for Mac computers - Downloads) if not changed. Alternatively click on the link using the right-hand-side mouse button and select option Save Link/Target As...chose folder where to save it. If it does not work, please make a copy of the link without any line break and paste it in the address line of your favourite internet browser and hit Enter key on the keyboard.

Some computer protection programs may prevent you from download setup files from the Internet. All Avanquest software have been scanned for viruses on many stages along the developing process and are clean of such. If the file can't be downloaded successfully we advise you to temporarily disable computer's protection program and to try again.

If you don't feel comfortable to do so, use protection program settings to exclude folder from being scanned. 
Here is an example where to find these settings in some popular antivirus programs: Avira, EMSI, Viper, Norton, AVG, Avast, Malwarebytes, Kaspersky, Webroot, Trend, Bitdefender, Microsoft Security Essentials, Windows Defender, McAfee, Panda, Bullguard, Symantec Endpoint protection, Advanced SystemCare Ultimate 9, ESET 

After the download is complete, click with the right-hand-side mouse button on the setup file and select option Run as Administrator.

Avoid typo mistakes by using copy-paste method to introduce the licence key and activate the software.

According to .pkg files on Apple computers, please read this useful article here.