Answers:-
1) Version compatible for Windows 7 are from 11.0.5 onwards where 11.0.6300 is the latest version which is also compatible.
2) You do not have to worry about the licenses as the licenses are just mere paper work and they are not be installed on the software by any chance.
3) uninstall the SEP version from the old laptop and then download the latest version from
https://fileconnect.symantec.com
Enter the serial number(M12345678)
And download the product and install the same.