Is there a limit to the number of layers in a Writer Doc

[SOS]

Different objects (Images , Shapes...) can been moved (Arranged) back en 
forward in a Writer Doc.

Bring to Front
Bring forward
Send Backward
Send to back

Our editors are some times confronted with a situation where Writer 
(after saving and reopening) lost the saved position (layer) of some 
objects.
When using multiple times "Bring Forward" or "Bring Backward" Writer 
seems to lose control over the layers, on screen it looks  correct but 
after saving and reopening some objects are moved to a wrong layer.
As a workaround and to repair ,we advised only to use "Bring to Front" 
and "Send to Back" who  limits the number of used layers.
So:
Is there  a limit on the used layers who can been saved?
If there is a limit, then a warning is needed to avoid the loss of layers.
Is it a  bug who must been reported ? but who is very hard to 
reconstruct because we never could lay the finger on the real problem, 
to many objects or to many layers ?

Greetz

Fernand