i dont know if this is already too late, but there are a few ways you can allow your customer to update this text (you mean the news text right?)..
one is to have the customer update text in a text file (news.txt, for example) and all the customer has to do is place this updated text file back on the server.....
or creating a small database and using PHP to call up the info in the database. with this way, you can create a html administrator site (a formular) for this customer and all the customer has to do it go to this administrator site, write the info into a form and this text will automatically be written into the database and will be shown in the flash site.
both of these possibilities have been explained either in the forums here or in tutorials, i believe.