I encountered a similar RangeError: [Error #1125: Index out of bounds] while listening for MouseEvent3D events when PlaneGeometry.doubleSided=true.
This is caused by an incorrect amount of the primitive’s uv coordinates. I fixed it by inserting this line of code in PlaneGeometry.as
override protected function buildUVs(target : SubGeometry) : void
{
var uvs : Vector.<Number> = new Vector.<Number>();
var numUvs : uint = (_segmentsH + 1) * (_segmentsW + 1) * 2;
if (_doubleSided) numUvs *= 2;
[EDIT]
Although this fixes the RangeErrors, it will not correctly calculate the uv coordinates and therefor still display the texture incorrectly.