I do not know either I have violated any rules or not. For transferring fund to any gambling site can be a reason for temporary disable of my coinbase account?? I do not think they disable account for sending fund to gambling site. Are you sure that they disable account for transferring fund to any gambling site??
Base on the experience of some of their users, and based on their terms, it's a Yes.
By opening a Coinbase Account, you confirm that you will not use your Coinbase Account and/or any Coinbase Services to do any of the following:
[...]
5. Gambling: Lotteries; bidding fee auctions; sports forecasting or odds making; fantasy sports leagues with cash prizes; internet gaming; contests; sweepstakes; games of chance
Now, if you really use your CB account to deposit or transfer btc to any gambling website then I guess it might be the case.
[EDIT] Ah someone posted the terms related to gambling already, my bad.
If they block my account then where the fund will goes? Do they usually lock all the fund or they will send the fund to any wallet other than coinbase. Several months ago I have heard that coinbase disable account and they give option to withdraw fund to any wallet except coinbase. In that case they didn't disable login. But for my case they disabled my login.
You're lucky enough if they let your funds to be withdrawn and close your account, but if not then that's a pain in the ass...