So, I've got a map where you basically run around and grab up territories by touching beacons. Some territories are considered gun towers, and have a turret and a sieged siege tank there. All of these buildings/beacons are originally owned by Player 12 (neutral).

I'm wondering how I can make it, when they get control of the tank, to not be able to unsiege it? I know if I remove the siege tech for all the players that would do it, but I also use the siege tank as an actual unit, being able to siege and unsiege it. So im wondering, if I disable the option for siege for the 12th player (if thats even possible, theres an option to do it, but I ha ve doubts that it will hold), and then give the unit to a player, will the lack of siege ability stick? Or will it be able to unsiege due to the player having the tech to do so?

The best solution would be to make seige unresearchable, but enabled. Use hero tanks for tanks that are supposed to fight and regular seiged tanks for ones that are the territory markers.

All tech and upgrades are player based. All units of the same player have the same tech and upgrade statuses.
Heroes always have their abilities researched, but that doesn't influence the tech status of the player. When you give non-hero units carrying a tech that is not disabled for the target player to him he will automatically research this tech, so all other units have this ability too.

I think the best solution would be to remove the tank if it is unseiged, and then just replace it. Other methods don't work very well with how you want to be able to use normal tanks too.