Randomly I have an issue with the time line where an object I am trying to move get placed on the same line with another object. I did not get a screen shot but I will try next time it happens.
I hate it when that happens. I find it typically only occurs when I have a ton of objects on the slide and I need to move a bunch of stuff between layers.
I usually just navigate to a different slide and come back and its fine again.
In less frequent cases, I save and close out of Captivate and launch a fresh session and it is fine.
Refresh glitch... not the onlyone.
I find if I drag layers to move (re-order) them, odd things can happen. Now I just use the layer controls on the toolbar. A bit more cumbersome, but worth it.
I have had toolbar controls cause the same issue too but it is always limited to high object volume slides.