To change the distance between the items you need to override the ItemsPanelTemplate of the CoverFlow.

Currently, the CoverFlow control uses our AutoCenterPanel that has a property called ArrangeStrategy. This property is currently set to PositionsBasedArrangeStrategy (the only one available and supported by us at this time). This strategy also exposes a property called PositionDefinitions that is a collection of PositionDefinitions. Supported definitions at this time are RelativeWidthPositionDefinition and FixedWidthPositionDefinition that tell the CoverFlow how much room it holds for each item.
The first one is for the centered item, whereas the second one is for the left and right items that are next to the centered item. The last one describes the rest.

In the project I am sending to you, you can find the XAML code that sets the current configuration (the ItemsPanelTemplate with key CoverFlowItemsPanelTemplate).

As for your second question - to change the orientation of the items (rotation angles, ZPositions, etc.) you need to override the ControlTemplate of the CoverFlow item. To accomplish this you can create a style for the RadCoverFlowPerspectiveItem and set its ControlTemplate in the style. In the attached example I am setting the currently used ControlTemplate.

If you have more questions, we will be happy to answer them.

Kind regards,
Miroslav Nedyalkov
the Telerik team