Created attachment 166044 [details]
Test file

Step to reproduce
Open test file
launch presentation
on the second slide, 4 text object should appears after each click

Go forward with right arrow key, after the first slide, the second slide is on the screen
Then after each hit on the arrow key, the the 4 text elements arrive on the good order (Q1 to Q4)

If you hit the left arrow  key, then it should removed the previously text.

i.e. if you have Q1 Q2 and Q3, when you hit the left arrow key, Q3 should disappear, if you hit the left arrow key again, the Q2 should disappear.
Then if you go forward with the right arrow key Q2 should reappear.

This is not the way it does

It works like this with OpenOffice. And it worked like this months ago

Same problem if you use a laser presentation remote

(Sorry for my so bad English)