I'm not the expert on this -- but my understanding is that CIC does not care that much about immigration violations in other countries. It would be difficult if you were applying for a TRV, because it shows that you are willing to break the law and are probably a return risk; but for FSW, that's not an issue, and your application shows that you are complying with CIC regulations. Even in the US, a visa overstay is a civil, and not a criminal offense; people who are bankrupt, or who have broken leases, are able to immigrate. Make sure that your answers to questions about visas are comprehensively correct -- but I wouldn't automatically assume that you need a lawyer.
Other people here can probably give you a real idea of how CIC regards cases like yours.