With latest git 7c377ba3852ca8c66e5d42bbdec7662ca9b7a4fd i get this backtrace while loading http://www.labottegadellabici.it/index.swf.

Loading stream: http://www.labottegadellabici.it/index.swf
SWFDEC: FIXME: swfdec_pattern.c(448): swfdec_pattern_do_parse: CAIRO_EXTEND_PAD is not yet implemented
SWFDEC: WARN : swfdec_shape_parser.c(279): swfdec_shape_parser_finish: fillstyle 0 has no path
SWFDEC: WARN : swfdec_shape_parser.c(279): swfdec_shape_parser_finish: fillstyle 0 has no path
SWFDEC: WARN : swfdec_as_interpret.c(568): swfdec_player_get_movie_from_string: "_level100" does not reference a movie
Loading stream: http://www.labottegadellabici.it/link.swf
firefox-bin: /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-pen.c:324: _cairo_pen_find_active_cw_vertex_index: Asserzione `i < pen->num_vertices' fallita.

Program received signal SIGABRT, Aborted.
---Type <return> to continue, or q <return> to quit---
[Switching to Thread 0xb718f920 (LWP 8714)]
0xb73707d6 in raise () from /lib/libc.so.6
(gdb) bt
#0  0xb73707d6 in raise () from /lib/libc.so.6
#1  0xb73720f1 in abort () from /lib/libc.so.6
#2  0xb7369b50 in __assert_fail () from /lib/libc.so.6
#3  0xb77b8f4f in _cairo_pen_find_active_cw_vertex_index (pen=0xbfe97070, 
    slope=0xbfe96f40, active=0xbfe96f48)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-pen.c:324
#4  0xb77b768e in _cairo_stroker_add_cap (stroker=0xbfe97058, f=0xbfe96f70)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-path-stroke.c:397
#5  0xb77b7945 in _cairo_stroker_add_leading_cap (stroker=0x0, 
    face=<value optimized out>)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-path-stroke.c:480
#6  0xb77b7976 in _cairo_stroker_add_caps (stroker=0xbfe97058)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-path-stroke.c:520
#7  0xb77b7d1c in _cairo_path_fixed_stroke_to_traps (path=0xa46ace8, 
    stroke_style=0xa46b4d0, ctm=0xbfe97518, ctm_inverse=0xbfe974e8, 
    tolerance=0.10000000000000001, traps=0xbfe97194)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-path-stroke.c:1024
#8  0xb77c11c5 in _cairo_surface_fallback_stroke (surface=0xa46aa10, 
    op=CAIRO_OPERATOR_OVER, source=0xbfe97454, path=0xa46ace8, 
    stroke_style=0xa46b4d0, ctm=0xbfe97518, ctm_inverse=0xbfe974e8, 
    tolerance=0.10000000000000001, antialias=CAIRO_ANTIALIAS_DEFAULT)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-surface-fallback.c:836
#9  0xb77be7ab in _cairo_surface_stroke (surface=0xa46aa10, 
---Type <return> to continue, or q <return> to quit---
    op=CAIRO_OPERATOR_OVER, source=0xbfe97598, path=0xa46ace8, 
    stroke_style=0xa46b4d0, ctm=0xa46b578, ctm_inverse=0xa46b5a8, 
    tolerance=0.10000000000000001, antialias=CAIRO_ANTIALIAS_DEFAULT)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-surface.c:1414
#10 0xb77b1379 in _cairo_gstate_stroke (gstate=0xa46b4c0, path=0xa46ace8)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo-gstate.c:975
#11 0xb77a9f4c in *INT_cairo_stroke_preserve (cr=0xa46ab78)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo.c:2053
#12 0xb77a9f72 in cairo_stroke (cr=0xa46ab78)
    at /home/rm/swfdec/cairo/libcairo-1.4.10/src/cairo.c:2027
#13 0xb0dbb66f in swfdec_stroke_paint (draw=0x9a782d0, cr=0xa46ab78, 
    trans=0xbfe97888) at swfdec_stroke.c:124
#14 0xb0d8a37e in swfdec_draw_paint (draw=0x9a782d0, cr=0xa46ab78, 
    trans=0xbfe97888) at swfdec_draw.c:129
#15 0xb0db6cce in swfdec_shape_render (graphic=0xa43e570, cr=0xa46ab78, 
    trans=0xbfe97888, inval=0xbfe97868) at swfdec_shape.c:63
#16 0xb0d98dfc in swfdec_graphic_render (graphic=0x220a, cr=0xa46ab78, 
    trans=0xbfe97888, inval=0xbfe97868) at swfdec_graphic.c:59
#17 0xb0d99135 in swfdec_graphic_movie_render (movie=0xa442e08, cr=0xa46ab78, 
    trans=0xbfe97888, inval=0xbfe97868) at swfdec_graphic_movie.c:49
#18 0xb0da067f in swfdec_movie_render (movie=0xa442e08, cr=0xa46ab78, 
    color_transform=0xbfe979c8, inval=0xbfe979a8) at swfdec_movie.c:895
#19 0xb0da0767 in swfdec_movie_render (movie=0xa4419e8, cr=0xa46ab78, 
---Type <return> to continue, or q <return> to quit---
    color_transform=0xbfe97b08, inval=0xbfe97ae8) at swfdec_movie.c:885
#20 0xb0da0767 in swfdec_movie_render (movie=0xa4417f0, cr=0xa46ab78, 
    color_transform=0xb0de6380, inval=0xbfe97be0) at swfdec_movie.c:885
#21 0xb0dac49c in swfdec_player_render (player=0xa2861e0, cr=0xa46ab78, x=309, 
    y=203, width=451, height=204) at swfdec_player.c:2249
#22 0xb20111c6 in swfmoz_player_render (player=0x8ea5150, region=0xa4671a0)
    at swfmoz_player.c:610
#23 0xb2011a94 in swfmoz_player_idle_redraw (playerp=0x8ea5150)
    at swfmoz_player.c:157
#24 0xb75f2611 in ?? () from /usr/lib/libglib-2.0.so.0
#25 0x08ea5150 in ?? ()
#26 0xb7e1f6bc in __pthread_mutex_unlock_usercnt () from /lib/libpthread.so.0
#27 0xb75f41c6 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#28 0xb75f7552 in ?? () from /usr/lib/libglib-2.0.so.0
#29 0x08bd26b8 in ?? ()
#30 0x00000078 in ?? ()
#31 0x0a26dad0 in ?? ()
#32 0x00000006 in ?? ()
#33 0x00000008 in ?? ()
#34 0xb7664aa0 in ?? () from /usr/lib/libglib-2.0.so.0
#35 0xb7664ae0 in ?? () from /usr/lib/libglib-2.0.so.0
#36 0xbfe97d64 in ?? ()
#37 0x00000001 in ?? ()