I don't know why, but magically after dozen of restarts and device restart right password appeared in tower's door interaction. Before it there was only two passwords: "My name" and another one started on "Me...", but no option like "Tremadan".
Thank you anyway for reply.
Did you stay at an Inn? Sometimes when something happens on a map (something appears, a door unlocks, a NPC is supposed to appear), that change doesn't occur to the map resets, which can be done by staying at an inn.
Yep, did 2 or 3 12h rests after first unsuccessful entrance try. Even after rest it still was "locked".
By the way, why teleportation scroll isn't working on tower? It works well with every city, but when tower choosen as destination point the game just says that "Spell failed!".
Both the teleportation scroll and teleportation spell take you to the room in the Tower with the bed. So --if my thinking is correct-- once you gain access to that room with the first elemental charge, you should be able to teleport to the Tower.