[v8i] unable to place center mark with extension lines

[v8i]

Hello,

The help dialogue for "Place Center Mark" (excerpt shown below) has an image at the bottom that shows a center mark and a center mark with extension lines enabled. I have never been able figure out how to place the center mark with extension lines active.

I have Extension Line Enabled in the Dimension Styles window and have hunted around in the Advanced tab for some setting that would help but have been unsuccessful. If anyone could provide a very specific instruction on how to make this work I would appreciate it!

Edit 9:53 14JAN14 To clarify, the center mark is always placed. The extension lines are the problem.

[I copied and pasted the image I referenced into this post, but the preview buttons showed it absent so I also inserted it. Image may appear twice or not at all.]