NT Licensing Maintenance

Hi folks;
I would like to know about the following:

1) How to maintain windows NT 4.0 Licensing and SQL Server 6.5, 7.0 licensing?
2) How to clean up the log file where it keep tracks the licensing information?
3) How to know when to use Per seat or Per server licensing?
4) if the no of users increase than the license allocated, how to limit the no of users for per seat licensing?
5) If we delete some license using Licensing utility, it appears again on the licensing tool, if the no of users acceed the no of license allocated?


Thanks in advance!!