When video is opened I got an error dialog saying: 
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Could not open the file /home/rafal/James Bond/20 - James Bond 007 - Die Another Day CD1 (2002).avi.

An unknown error has occured. Please report a bug and include this error name: "System.FormatException".
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It doesn't matter if subtitles are opened or not.

On console there are following:
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mplayer: could not connect to socket
mplayer: No such file or directory
Failed to open LIRC support. You will not be able to use your remote control.
open: No such file or directory
[MGA] Couldn't open: /dev/mga_vid
open: No such file or directory
[MGA] Couldn't open: /dev/mga_vid
[VO_TDFXFB] Can't open /dev/fb0: No such file or directory.
Using SSE optimized IMDCT transform
Using MMX optimized resampler

(GnomeSubtitles:4155): libglade-WARNING **: unknown property `text' for class `GtkMessageDialog'
System.FormatException: Unknown char: .
in <0x00052> System.Double:Parse (System.String s, NumberStyles style, IFormatProvider provider)
in <0x00011> System.Double:Parse (System.String s)
in <0x00014> System.Convert:ToDouble (System.String value)
in <0x0001e> GnomeSubtitles.Player:GetAsFloat (System.String command)
in <0x0002b> GnomeSubtitles.Player:GetLength ()
in <0x0004d> GnomeSubtitles.Player:Open (System.String filename)
in <0x0002c> GnomeSubtitles.Video:Open (System.String filename)
in <0x00046> GnomeSubtitles.GUI:OpenVideo (System.String filename)
mplayer: could not connect to socket
mplayer: No such file or directory
Failed to open LIRC support. You will not be able to use your remote control.
open: No such file or directory
[MGA] Couldn't open: /dev/mga_vid
open: No such file or directory
[MGA] Couldn't open: /dev/mga_vid
[VO_TDFXFB] Can't open /dev/fb0: No such file or directory.
Using SSE optimized IMDCT transform
Using MMX optimized resampler

(GnomeSubtitles:4155): libglade-WARNING **: unknown property `text' for class `GtkMessageDialog'
System.FormatException: Unknown char: .
in <0x00052> System.Double:Parse (System.String s, NumberStyles style, IFormatProvider provider)
in <0x00011> System.Double:Parse (System.String s)
in <0x00014> System.Convert:ToDouble (System.String value)
in <0x0001e> GnomeSubtitles.Player:GetAsFloat (System.String command)
in <0x0002b> GnomeSubtitles.Player:GetLength ()
in <0x0004d> GnomeSubtitles.Player:Open (System.String filename)
in <0x0002c> GnomeSubtitles.Video:Open (System.String filename)
in <0x00046> GnomeSubtitles.GUI:OpenVideo (System.String filename)
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Mplayer version: mplayer-1.0rc1-2
System: FC5, i686
Kernel: 2.6.20-1.2300.fc5 (from fedora-updates repo)
Glade: libglade2-2.5.1-4.fc5.1
       glade2-2.12.1-2