As quoted we will reopen in around 24 hours and let people withdraw all their coins and currencies in manual mode (so we can check each withdrawal and delete some abuse users we didnt noticed yet).
Will this withdrawals be obligatory or my coins can stay on exchange?
I'm going to guess and say this:
Neotrix is allowing anyone who would like to get their coins out, a chance to do so. This is to lessen the already bad situation; to show that they are working on the problem and have the customer's money on hand to facilitate withdrawals.
However, if you feel safe keeping your coins on the exchange, I'm sure it won't be a problem for neotrix and his crew for you to leave them there.
Again, I don't speak for neotrix. What I just said is my guess after looking at the situation.
But if everybody will keep coins on the exchange then how they would "check each withdrawal and delete some abuse users we didnt noticed yet"?