I'm using OO 3.1 on a WinXP Sp3.

I created a bullet-pointed list of text items in a text box, organized as
level-1 and level-2 items, then I assigned a custom animation in order to apply
dissolving effect on the list based on level-1 items.

My intention was to have the list appearing a piece at a time, level-1 item by
level-1 item. Level-2 items should appear together with level-1 ones.

To achieve this I selected "level-1 paragraphs" from the "group text" option of
the Effect Options dialog, for my text box.

In the Custome Animation pane, I can see that the animation order is correct and
level-1 items are to start AFTER the previous item, while level-2 elements are
correctly assigned to start TOGETHER with the previous item.

I added delays of 2 seconds on the level-1 items, so they have a pause from one
to another.

The problem is that Impress changes the way it renders this animation
unpredictably, each time I run the presentation. Usually, it renders level-2
items before the corresponding level-1 item.