If you were a registered member of the old board and requested a temporary password in order to log on, the system will automatically generate a random password for you that you can enter to log on and then change it.
However, a lot of people registered either with old, now-out-of-date addys or the address was invalid to begin with. The other system didn't catch this. This one does. Better security. So if you are not receiving a password reset email when you request it, it's for one of those two reasons. The system doesn't have the right email address.
If this happens to you, email us at firstname.lastname@example.org and we'll manually plug in your valid email address and give you a temp password to get you going.