Well, for me there are things there are illegal but I can't find anything morally wrong in them.

One may legitimately have a moral obligation to break the law. Work the logic from there.

No, morality and legality have separate concerns. Morality is concerned with what one ought to do regardless of punishment or reward, legality is about conforming to laws which may have punishing consequences for non compliance.

Justice and morality are sufficient and necessary conditions for a functional society.

"Justice is a broad concept that is based on equality of rights, fairness and morality. Conversely, law is a body of regulations and standards set up by governments and international bodies and is (or should be) based on the idea of justice. Laws are written norms that regulate the actions of the citizens and of the government itself in all aspects, whereas justice is a principle that may or may not be universally recognized."

Morality is a work product of society. The first time two people had to coexist or cooperate, morality was born. Before that, it was irrelevant.

Society expresses and enforces it morality in various ways and the legal and penal systems are one of them. Like all human enterprises, societal morality is not perfect and ever-evolving, and the legal system isn't perfect and is ever-evolving. Therefore ... not all laws are just and not all enforcement is just. That's why for example people (most particularly black people) are sometimes shot in the back while performing the incredibly threatening move of running away from police after committing heinous crimes like having a tail light burned out -- and the shooter gets away with it, basically because they're the police.

There was a time when it was legal to own slaves and illegal to have an abortion; those two things have flipped 180 degrees since that time. This is because the foundation of morality -- the harms or benefits certain activities are generally accepted to have on civil society -- is something our understanding of is constantly improving. We can therefore deduce that there are surely injustices that we're blind to today, that we won't be blind to 50 or 100 years from now. And there will always be morality that are not written into law or that are not well expressed in legal terms, or that are not fairly and equally enforced for all.

No.

Short opinion - Both what's immoral and what's illegal is dependent on too many variables.

Long opinion - For someone smarter than me, which isn't difficult.