The license as listed on the site is for UBB.threads licenses sold by Infopop only.
Grandfathered WWWThreads licenses are permitted to run under their old conditions, including powered-by removal and multiple boards on one domain. Not all grandfathered licenses have the same terms. You should open a support ticket and ask for the exact terms that you are covered under if you have any questions.
So in your case, with your WWWThreads license, you can run mydomain/forum/, mydomain/gaming/, etc... however, if you wished to make a new installation on another domain, you would have to have an Infopop-provided license, and follow the terms it sets forth.
For the two questions you pointed out...
1) I see no reason why that would ever be needed - the intent of the license, and that line in particular, would basically require that each of the script installations point at the same exact content. There is no logical reason to have multiple installations in different locations pointing at the exact same data. (Except in case of load balancing, which I believe is expressly permitted elsewhere in the license.)
2) Only if each of those installs has a current license -OR- if that domain is covered by the grandfathered WWWThreads license terms.
For what Conrad wishes to do, each domain would need its own license - the intent of the license is to permit one board to run per license. Doing this, even with only one copy of the software and one database, with the intent to create the effect of multiple boards, would probably be viewed as a violation of the license.
