swf2pngs allows you to convert SWF into PNG. Assign the first frame that you need to the variable and name it "pngfilename". If you need to start from any other custom frame, just assign it to "pngfilename" in left-bottom corner. Export swf, pick the name, click start, and wait for result.
What's new in this version:
Version 1.3.9 fixes some bugs.