Sounds like you've missed some prerequisites somewhere. If Mournhold is still black, you haven't yet completed "The Mournhold Underground", and that's a prerequisite for most of the eastern Deshaan quests. Try looking for Naryu Virian at the House Dres Farmstead.
You also need to have completed Obsidian Gorge in the west and turned that white.

Rainsorrow wrote: »

That's the problem - I did some quests in mournhould (I guess it was mournhold underground because I was in sewerage or somewhere there, even did some quests on Farmstead...I even got "Almalexia's Enchanted Lantern" trophy and curretly sitting on 51/55 quests completed in Deshaan zone

I don't know about Mournhold, I do remember being in your situation multiple times on different locations. Trust me, the quest is somewhere out there, just a pain to find sometimes.

There are more then 55 quests by the way. It's just the achievement goal.

Enodoc wrote: »

Somewhere else to check is inside the Tribunal Temple; is that icon still black? Is there any text with that icon?

Black too, inside there is no quest, even Almalexia is not visible there

Rainsorrow wrote: »

Hello everyone. I have checked entire Deshaan zone multiple times, yet i can't find any more quests. Mournhold is still blacked out with "Find out what's happening in the city of Mournhold", Eidolon's Hollow (was only one quest there) and Shrine of Saint Veloth "Restore Saint Veloth and stop the Daedric incursion" (same, only one quest with killing watchers).

If there was only one quest in both of those locations then you haven't completed the prerequisite quests that are supposed to send you there.

If you have received Almalexia's Enchanted Lantern, then you've definitely got to the point just before the Mournhold Underground quest, and since you say you remember going around the farmhouses and going into the sewers, it sounds like you at least started that quest. I suspect that somehow you didn't complete the quest, though, because after you've done that you're supposed to talk to an Ordinator in Mournhold who will give you your quest reward (which should complete the Mournhold objective), and send you back to Almalexia for the next quest, which will lead to you completing the Tribunal Temple objective, and then send you off to Selfora, after which you'll go to the Shrine of Saint Veloth and be able to do the main quest there (you've already done the side quest), and then to Eidolon's Hollow to do the last quests in the Deshaan main questline.

Rainsorrow wrote: »

edit - bizzare, i get mournhold underground quest, even that i knew i did it before

Probably something bugged and the quest didn't complete properly the first time around. From your description of what you had and hadn't done, I suspected that either you had simply missed handing the quest in somehow (although then it should have still showed in your journal), or that it didn't complete properly and got dropped.