Several InlineGraphic Bugs

InlineGraphics are not always displayed on load if in several paragraphs, dis- and reappear when editing the paragraphs/TextLines they're in and errors occur when trying to navigate to "hidden" InlineGraphics
please execute attached code for demonstration.
After loading, the movie only displays the flash logo and the red rectangles. If you place the cursor somewhere and keep [Arrow down] pressed, the errors (tracebacks below) occur.
then, if you edit the "xyz" the blue rectangles do appear.
Now scroll down until the graphics are off the screen. When you scroll back and select one of the graphics (or text within the same paragraph), they disappear, but still occupy space and are selectable. Editing in their respective paragraphs causes them to reappear.

using TFL from gumbo 4.0.0.5313

An ActionScript error has occurred:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at flashx.textLayout.container::ContainerControllerBase/posToRectangle()
at flashx.textLayout.container::ContainerControllerBase/scrollToPosition()
at flashx.textLayout.utils::TextRangeUtil$/nextLine()
at flashx.textLayout.edit::SelectionManager/handleDownArrow()
at flashx.textLayout.edit::SelectionManager/handleKeyEvent()
at flashx.textLayout.edit::SelectionManager/keyDownHandler()
at flashx.textLayout.edit::EditManager/keyDownHandler()
at flashx.textLayout.container::ContainerControllerBase/processKeyDownEvent()
at flashx.textLayout.container::ContainerControllerBase/keyDownHandler()

An ActionScript error has occurred:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at flashx.textLayout.container::ContainerControllerBase/posToRectangle()
at flashx.textLayout.container::ContainerControllerBase/scrollToPosition()
at flashx.textLayout.utils::TextRangeUtil$/nextLine()
at flashx.textLayout.edit::SelectionManager/handleDownArrow()
at flashx.textLayout.edit::SelectionManager/handleKeyEvent()
at flashx.textLayout.edit::SelectionManager/keyDownHandler()
at flashx.textLayout.edit::EditManager/keyDownHandler()
at flashx.textLayout.container::ContainerControllerBase/processKeyDownEvent()
at flashx.textLayout.container::ContainerControllerBase/keyDownHandler()

An ActionScript error has occurred:
RangeError: Error #2006: The supplied index is out of bounds.
at flash.text.engine::TextLine/getAtomBidiLevel()
at flashx.textLayout.elements::TextFlowLine/adjustEndElementForBidi()
at flashx.textLayout.elements::TextFlowLine/makeSelectionBlocks()
at flashx.textLayout.elements::TextFlowLine/ http://ns.adobe.com/textLayout/internal/2008::calculateSelectionBounds()
at flashx.textLayout.elements::TextFlowLine/getSelectionShapesCacheEntry()
at flashx.textLayout.elements::TextFlowLine/ http://ns.adobe.com/textLayout/internal/2008::selectionWillIntersectScrollRect()
at flashx.textLayout.container::ContainerControllerBase/scrollToPosition()
at flashx.textLayout.utils::TextRangeUtil$/nextLine()
at flashx.textLayout.edit::SelectionManager/handleDownArrow()
at flashx.textLayout.edit::SelectionManager/handleKeyEvent()
at flashx.textLayout.edit::SelectionManager/keyDownHandler()
at flashx.textLayout.edit::EditManager/keyDownHandler()
at flashx.textLayout.container::ContainerControllerBase/processKeyDownEvent()
at flashx.textLayout.container::ContainerControllerBase/keyDownHandler()