I used to follow zek then i swopped to karana i wanted to swop back and have renoucned karana however the zek priest wont talk to me clicking the zek alter does nothing in the guild hall or the zek alter in BBlock. Anyone experienced this before ?
You didn't betray over to good alignment at some point, did you? Do any of the other evil deities allow you to worship them instead? Try Innoruuk at the Greater Faydark Spires, or Cazic Thule over by Unrest in Butcherblock, or Bertoxulous in Gorowyn, or Anashti Sul at the Sinking Sands docks. If any of them will let you take them, then I'm not sure why the Zek deity won't.