If the demo version closes immediately, then the most likely cause is, that the trial period is expired. A dialog should tell about this.
If no dialog appears at all, please contact our technical support and inlcude any errror messages related to our products that you find in the Windows Event Log under "System" and "Application".
Most likely, it was the installation key of an older version. Installation keys change with every new major version published. In case of doubt, the one in your customer account is the current one.
Failed Updatedownload may have the following reasons:
The downloadserver is temporarily not available.
Security settings: Firewall, TLS/SSL from internet options prevent the download.
Your Internet connection is broken.
Please check your settings and try it again.
Alternatively you can download the update manually in the "Customers Area".