The 2d topograph didn't work

[sherry]

[img]C:\Users\sherry\Desktop\1.JPG[/img]
This is my scenario.
And I use the openvibe/share/electrode_sets/electrode_set_standard_cartesian.txt as the eletrode location file.
When I push start, I can get the signal, but the topograpy is black...
[img]C:\Users\sherry\Desktop\2.JPG[/img]
It's my first time using this software, so can anyone tell me what's wrong?

by the way, how to add a picture?...

[sherry]

Does this software has some requirements for the computer graphics?