Behavior: I can select the lines I need to dimension, the value appears but there are no leader/dimension lines. When I click to place the dimension, it just disappears...Diameter dimension works OK.
That does sound strange. Have you tried placing the dimensions, then closing the drawing and reopening it? I personaly have seen this kind of thing. Dimensions seem to disapear as soon as you place them. Then close and reopen the drawing and there are multiplue copies of the same dimension.
The same thing happened to me, I thought it was me at first. I started a sesssion with the Assistant. He had trouble figuring it out. It is currently "under investigation" incident # 836687, if you want to ck on it.
Pete