Town Portal bugs?

To answer your last question/problem the Advanced Town Portal spell says in the description that it teleports you to the nearest friendly town with an Advanced Town Portal building.

Your Advanced Town Portal spell is probably grayed out because you are already in the town it would teleport you to, so casting it would do nothing. You can test this by taking a step away from your town and see if the spell is available again.

From your description it does sound like you should be able to use the Basic Town Portal spell to teleport to your other town. You should make sure that the other town does not have two hero in it. If the other town is completely occupied, you will not be able to cast the spell.

If the target town is not full and and you still cannot cast the spell, it is probably a bug, so you should try saving and reloading to fix the problem.

As the others have said, you cannot use either Town Portal spell to teleport to the fort anyway because the spells only allow you to teleport to towns, and forts are not towns.

You cannot use both Advanced Town Portal and Basic Town Portal on the same turn, even if you have the necessary movement points.

There are a couple possibilities here:

• Is the town portal basic effect cursor coming up at all? (Looks like the same symbol for Magic Power) If it's not coming up at all, that's likely a bug. Your best bet is to simply quit / reload the game.
• If the cursor is coming up, and your target is valid, you've likely just triggered one of Heroes' VI's many bugs, and you best bet is reloading / restarting the game.

It's a bug.

You need to go back to a save game when you still can use town portal advance. If you don't have one, you're going to have to restart the campaign.

It can happen to any faction campaign; It's not about gameplay tactics, it's about how unlucky you are.