Hi,

i just took truncuillius or however he is spelled into custody. I did all locations and all quests but somehow i can't proceed.
What to do next?

Did you bring all heretics in Glatzburg to justice and burned them?
Can you travel to Alvaron? It just appears on the global map when you're done in Glatzburg.

Ye i did. The lady and 2 others. I cant travel to Alvaron. All i can do now is torture trancuillus but he's not saying anything.

Do you have his letters? You need them to accuse him. Tinthan can help you with acquiring them. Torturing Tranquillius doesn't help you because he already confessed to you in the church, it will only decrease your alignment!