Returns or sets the active layer (the index of the layer returned by CurrentLayer).
The first layer has the index of 0, the last is LayersCount - 1.
Making a layer current changes the IEBitmap, so it points to the current layer (allowing specification of which layer is active for input/output and image processing operations).
Note: ◼Use CurrentLayer to return the layer object. Use LayersCurrent to get or set the current layer by its index ◼Setting LayersCurrent does NOT deselect existing layers (if multiple layer selection is enabled)