DT Register works in conjunction with the JEvents component. Anything you setup in JEvents as an \"event\" can be setup for registration in DT Register. Doesn\'t matter if it\'s an online event or not. As to your second question, I\'m not sure what you are asking. Please specify what exactly you are trying to hide or restrict.
We will have multiple online events on the site. Is there a ticket or something that will restrict someone that signed up for event x to be able to attend event y?
I\'m still unsure of what you are asking here, but there is no manner currently that will restrict anyone from registering for an event due to already being registered for a different event... if that is what you are asking. There is a duplicate registration function you can opt to use that restricts someone from registering more than once for the same event.