I've attached two screen shots of how Identity Broker 5.0.1 is rendered in IE8, which according to the documentation is supported (IE8+). I've had access to two systems with IE8, both of which exhibit these symptoms. The first being a Windows Server 2008 system and the other a clean install of Windows 7 that I made in Azure specifically to see if this issue was reproducible.
As can be seen below, quirks mode is functional but misformed. In standards mode much of the page is obscured by the upper pane, including most of the controls associated with the connectors or adapters pages.
In both cases Identity Broker is running on the embedded web server. Screenshots taken with 8.0.7601.17514 of IE.
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