[ubuntu_studio] Problem with monobristol GUI

Hi

after install Monobristol (GUI to launch bristol synths)

when i launch it in terminal, I get the message :
"Caot open assembly '@expanded_libdir@/monobristol/monoBristol.exe':File not found"

I can launch each of the synth by typing startBristol -nameOfTheSynth (startBristol -b3 , for example)
but not the GUI.

I have seen in Synaptic package manager that some package used by monoBristol are broken, and they don't repair when i click "repair broken package"

Any Ideas ?