This is not a defect but an enhancement.

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Many thanks,
Andrew
 
Cleaning-up and Closing old Issues as part of:
~ The Grand Bug Squash, pre v3 ~
http://marketing.openoffice.org/3.0/announcementbeta.html

dupe of #55729 ?

No, this has little to do with issue 55729 IMHO: it is a simple problem of
sensitive UI configuration of Impress: while some parts of the OO UI remember
specific user arragements are saved(e.g. the toolbars: you open/close your
favourite ones, place them where you prefer, and they will stay there from then
on), appearance of the two lateral panes in Impress (left: slides pane, right
animation and others pane) will always, stubbornly reopen in the same default
way. If you want more space for editing, for example, you could rather have the
animations (right side) pane stay normally closed or squeezed to the right until
you positively open it. But no way: you'll have to reclose it 100 times if you
open a file 100 times. The same lack of "memory" concerns the choice if the
front page for the right-side panel: you could like to have the animation page
in front, but there is no way it will always open with the "layout" page in
front, and you have to switch times and times again.
Of course it's only a question of ease of use....

Seems similar to Issue 96290.

Yes and no, Issue 96290 is concerning an object that has its own "memory", i.e.
it remembers its visualization settings, but if I understand correctly, keeps
this settings across all OO apps even if its presence is welcome in only one of
them. So you open the navigator in writer because in that app it is useful, you
do not want it in calc but the on/off switch is unique and you get in in calc.

The present issue concerns instead objects that have NO memory: they are
application specific (Impress) so there is no problem like the one above, but
there is no way to make the app remember if you want them open or closed, as
well as if you want them to open in a certain way (i.e. which pane to visualize
by default) when you open them. No matter how you settle them when working with
Impress is open, next time you run Impress again (with the same file or another)
they are always and invariably OPEN, and open in the same default way.

Well actually this it is not 100% true, as the one thing they remember is size:
you can resize them to your tastes, and from then on they will keep that size. 
Notice that, on the contrary, the "hidden" state (i.e. what you get when you
click at their internal border, causing them to stay open but show only that
border on the extreme right (the "activities" pane) or on the extreme left (the
"slides" pane). 
I hope this help to clarify the matter and to answer comments from hagar_de_lest