I saw that thread: SWFTools Segmentation Fault
When I tried to convert a PDF to SWF using pdf2swf I got an error:
/usr/local/bin/pdf2swf /var/www/html/ny
The levels are
-O 1 == -s poly2bitmap
-O 2 == -s poly2bitmap -s bitmapfonts
-O 3 == -s poly2bitmap -s bitmapfonts -s ignoredraworder
This probably means that there is crash converting vector art / letters into simpler vectors for Flash. I haven't worked with swftools for a while (not since it used libart for that sort of thing) but we generally had fewer problems with using very recent snapshots or CVS rather than numbered releases in case that helps.
I tried -O 2 and it worked, but the swf page is bitmapped only:
pdf2swf my.pdf -O 2 -o my%.swf
% outputs 1 swf per page of pdf.