rvc7 - background mode

[joko]

the background mode does not work for me. I enabled the background mode in the settings and closed RVC after this change. But RVC does not reopen in background mode as described in the demo. Starting RVC again I get the message "background mode cannot be setup! Right click your desktop then click Personalize and select a Windows Aero theme".
But I use already a Aero theme for Vista.
What can be the problem ?

With which Aero theme can somebody use the background mode ?