Manafort worked for the corrupt Ukrainian government and Russian oligarch. These corrupt people keep their money in Cyprus, and they like to pay their corrupt lackeys by bank transfers from one Cyprus account to another. Gates set up these accounts for him Manafort then corruptly transferred millions of dollars out of his Cyprus bank account to fund a lavish lifestyle ($360,000 rugs, for example), apparently to evade taxes and perhaps to hide the source of his money. One bank closed his accounts because they believed he was money laundering.
Despite being immensely wealthy from his ill-gotten gain, he was actually in deep debt during the time he worked free for Trump. He kept one step ahead of the banks by performing elaborate shell games with all his loans and mortgages. A lot of people helped him or at least knew what he was doing. Most of those people's names are blacked out, but presumably they are witnesses against him. So crimes are money laundering, tax evasion and bank fraud.
He didn't register as a foreign agent. They have documentation that he knew in at least 2012 he should have. Gates knew too. So willful FARA violation.
There are multiple pages blacked out. I speculate that this is information related to the Trump campaign. I further speculate that Manafort's accounts were being used to transfer money from Russia to pay people for illegal campaign activities in the United States, or to transfer money from the US to Russia. This would have been a good way to get around sanctions against Russian oligarchs.