Transitions Between External SWFs

hello to everyone
i am trying to get working an example found here http://www.kirupa.com/developer/mx2004/transitions.htm
this works fine but…
when exporting swf there seems to be a empty sceene for a moment between the transitions (smth like a blank frame).
this is why i tryied to do the exact steps a couple of times but the problem insists.
any ideas why???
i have been trying to do this on my own for weeks but then stood lucky and found it here,
so please help me understand what i am doing wrong :frowning:
thanx in advance