I am new to CB

Want to use CB but have such question:

running production 1.5.3 j site with some members, what will happen if I install cb ?

these users should register one more time or what?

I should delete them? or ... and etc.

Can someone explain how things goes on? thanks

there's a button in "tools" to syncronise the users. not used it, but sounds like it's what you want