Can't get at a button with AS (wtf!?)

I’m trying to get at a button to do some onRelease stuff - it’s path is be

_root.contentObjects.mcTopRight.btnNewer

but I just can’t get at it in any way shape or form. I can do stuff with it with actionscript attached directly to the button but I can’t call it.

I believe this could be because the button is in an imported swf (loaded into contentObjects)

I tried placing a button on the root of the swf and accessing that (would have been _root.contentObjects.testButton) but I can’t even get at that.

Pleeeeaaaase help