Hi
1- I run “OOo Impress†and made a presentation.
2- “Locale settings†of my “Impress†is specified to Farsi language (I'll attach
a screenshot for better description) As you know text direction in Farsi
language is RTL.
3- I went to my office and opened my presentation for my boss. It was  very bad!
All of my slides represented with LTR text direction, and my presentation showed
in disorderly positions. 
4- After a double check, I found cause of this issue. “Locale setting†in OOo of
my boss was specified to English language and as you know text direction is this
language is LTR. I specified his “Locale setting†to “Farsi†language and thus I
solved this problem.  
After this problem I had an idea. I think the best way to solve this issue is to
save locale settings into the document and load user-specific settings with the
document.
Although there is same setting in OOo options (in Load/Save section) but it just
save general settings. Maybe you will say that if we save settings as I said,
the saved document will be bloated. 
There is a solution to avoid this problem. You can put this feature as optional.
It means that if the users need it, they can select or vice-versa.
Thanks