Hans,
You can check the value of the Speed property of the 1st behaviour of the
motion path. +'ve or -'ve value determines the path direction.
?Activepresentation.Slides(1).TimeLine.MainSequence(1).Behaviors(1).Timing.Speed
-1
However, while you can use the above property to determine if the path is
reversed, there is no way to set it to a negative value in the OM since it
will throw an error.
Only way to change the direction programmatically is to rearrange the actual
motion path coordinates.