guild wars: How do I get other classes of characters to other campaigns? + help with Nightfall glitch?

Question

I've seen classes from the other campaigns in a campaign which originally did not have them. I was wondering how to do this?

Also the nightfall campaign doesnt allow me to go past the first town. I get to the town and when I select to go after the enemy army it instead restarts my computer. This is the only mission that has done that while I have played guild wars.

@Alinab: while your answer has knowledge to it it did not answer either of my questions.

Answer 1

If you own more than one campaign ON THE SAME ACCOUNT it is possible for characters to move from game one to another. You need to go to a specific city in each game. In that city there will be a quest that allows you to travel to the linking city of another game.

Propocies = Lion's Arch
Factions = Kaineng City
Nightfall = Conuslet Docks
(Also there is usually an entrance into Eyes of the North near those locations as well.)

The quest fot the transfer is difficult, so only high level chracters with friends should attmept it.

As for your second quetions, I can't really help you. I'd e-mail GWs and try to find out what's wrong.