I have a question about using tab Index and making an flash application accessible!

I have one main SWF in which I load some 10 different SWF's one by one. For this navigation I have a 'back' and 'next' buttons for which I have set tabIndex to 1 and 2 respectively. Now again the external SWF's which load inside this main.swf has tabIndex properties set from 1 to n..........

Can some body determine how the order of focus shud be.....and It would be great if you can share some more info about the same!

As ever,
Vinayak Kadam