Hi all,
i have two questions regarding the use of layers.

 -- Is there an easy way to position a layer in the middle of the page.
    My intent is to position some kind of graphic/picture there.
    I usually try to wrap the picture in a "hbox to \paperwidth {\hfil \externalfigure{} \hfil} and then
    wrapping the hbox in a vbox
         -- Is there a better way to achieve this?
         -- How to do that with layers?

-- Is it possible to define and position layers in one Macro. I have something like the following
   in mind (untested):

   \define[1]\MLayer{
      \definelayer[#1]
      \setlayer[#1][state=start]{\externalfigure[#1]}
    }
    My experience so far is, that it's necessary for a layer to appear that it is listed in "pagebackgrounds"
    ist this true? With this it seems, that a macro like that above is impossible, true?
   
thanks in advance for your help

Erik