Export / publish image (jpeg)

i have an ennoying habit of designing print in flash
now i made a poster in flash and now want to export it in 300 dpi
this means a jpeg of 7125 x 4987 pixels

but flash doesn’t render the whole poster
it leaves out half of the image
i have to take it down to 170 pixels for it to put in all the elements that are on my stage

any ideas how i can solve this?
a program that supports swf in which i can import and then export to jpeg?
or some way to make flash do it properly?