The International Criminal Court probably helped the founding of South Sudan when charges were brought against the Sudanese president. The court helped in that it formed a new country, but now there is civil strife in South Sudan. The new country is free of one dictator but now faces its own strife.
The problem with international courts is that they only try heinous criminals after they have already committed enough atrocities and crimes for the rest of the world to notice. It is great to bring people to justice, but trying them after the fact isn't very helpful to the people facing atrocities. Swift and direct international intervention would have been more helpful to Sudan than international trials years later.