Or is the downloader not able to go above 0%? In this case it could help if you disable your firewall or Windows Defender temporarily until the installation and registration of the software is done.
@Hugo-Hidalgo In which country are you living? There are some ISPs out there that allegedly block Magix servers. I'm not sure this is the case but it could help to use a VPN.
But you can also contact customer support at infoservice@magix.net and ask them for a direct download link. Then you don't need to use the download manager.