1) That functionality could be added, but it isn't built in. I'd suggest using a premier support ticket to work out the details if you aren't able to do it on your own.
2) Yes you could do this with the phpMyAdmin import and export utility, but if you are only copying some and not all it might be difficult because there are multiple joined tables and you wouldn't be able to easily import if the autonumber column values are already used in the database you are importing into. (a solution might be to add 10000 to each of the IDs in the tables you are importing from before import that way they would be higher than any IDs that might be in conflict.... this too we would be able to help with in a premier support ticket)