Hi Denherds,
Thanks for your interesting in Microsoft Fix it Center(Beta). Based on your description, please check your internet explorer proxy. You can complete the checking by the following steps:
1. Open Internet Explorer, then click Tools-->Internet Options.
2. In the Internet Option windws, select Connections tab, click on LAN settings.
3. In the Local Area Network Settings windows, check if you have a proxy for LAN.
If you don't have a proxy, please set a proxy whick can access the internet then try to install Fix it Center again. Please let know if any questions about this issue. Thanks!
Sam