I have configured Impress with the slide pane docked at the left side and the
task pane docked at the right side. Then I create a new presentation. The new
slide in normal view is centered into the free space between both panes and the
zoom factor is set automatically so that the entire slide is visible with some
small border. Lets say the zoom is 79%. 

Then I save the slide and reopen it: The normal view has still the zoom factor
of 79% and is centered, so it looks as before.

Now I change the zoom factor, eg. to 75%, edit the slide and save it again. When
the slide now is reopened, it is no longer centered between the panes and the
zoom factor has changed, e.g. to 80 %, so not all of the slide is visible in
normal mode. From then on at each reopen one has manually to readjust the
initial view that also seem to vary at random (I found zoom factors from 80% to
100%). 

This behavior is very annoying. Instead the view either when the file was saved
last should be restored, or at least Impress should keep the zoom factor
independent from the documents and always center the initial view.