Had a number of problems with this so decided to remove ADFS and re-install.
Un-installed it via Control Panel, removed the web site from IIS (Default Web Site) and deleted the adfs directory under inetpub.
When I ran the wizard again, all components correctly installed but the wizard complained that it found the web site so could not re-install. The message was "Existing web site detected".
WTF - I removed everything.
Mr. Google to the rescue and eventually I found the solution.
You need to run the command:
"appcmd delete app "Default Web Site/adfs/ls"
"appcmd delete app "Default Web Site/adfs/card"
"appcmd" runs under the command prompt and is found under "C:\Windows\System32\inetsrv".