If you've got two unrelated questions then please ask each in a separate thread (or at least a separate sentence 
).
The viewer pane can be on the right or on the bottom of the window. You can toggle its position by clicking the button which looks like an = symbol next tot the X close button for the panel. The viewer can also be opened as a separate window. Those are the only three options at the moment, so you can't have it in the little rectangle that would be below the folder tree and to the left of the file display.
For indexed searching, Opus can hook into Google Desktop but that's the only option at the moment.