Problem inserting flash buttons

When I try to insert a flash button into a previously developed web page, I get
a Flash "Icon" but not the button itself. This is true with flash text
inserted too. when I click "play" in the properties window, even the Flash icon
dissapears and then reappears when I click "stop." If I create a new document,
I am able to insert both Flash text and Flash buttons fine. I am running DW MX
on OSX. Can anyone help with this?