The goal of an early game build order is to have a very fast and powerful start, that can snowball the whole game and make playing Age of Darkness (AoD) much more pleasant.
To achieve that we will be aiming to build certain buildings and get certain upgrades as soon as possible.
Here is what we are aiming for:

• Early wood workshop to unlock tier 2 houses.
  
• Early keep upgrade to get more storage space and +100 gold income.
  
• Early tier 2 houses to boost gold income as much as possible

In best case scenario we should have everything by the end of 2nd day, however not every map and starting area allows for the optimal build order.

To achieve the build order goal, we need to have at least:

• 10 or more stone income from the 1st stone quarry.
  
• 32 or more combined wood income from 1st and 2nd woodcutters.

To have 10 or more stone income you need to scout and clear a stone area that has at least 5 tiles of stone. (1 tile of stone is worth 2 stone income)
And to have 32 or more wood income you need to have either 2 woodcutters worth 16 wood, or one worth 20 wood and another worth 12 wood or... You get the idea.

It is easier to find stone if you scout for it as soon as possible, exploring around the starting area in all directions.
To get enough wood it is best to try and look for wood lines.
An example of a wood line:

Currently in the game there are 5 base difficulties:
Easy, Normal, Veteran, Horrific, Nightmare.
There is no economic difference between them, however players can increase the base difficulty further with hardships.
Out of all the hardships, only Heroless and Veil Bond have an impact on economy.

• Heroless - you play without commanding a hero, you have additional +10 gold income from the start, because heroes have 10 gold upkeep.
  
• Veil Bond - you start with both heroes from a faction with their levels capped at level 6. Due to an additional hero you have -10 gold income from the start.

At the moment there are 3 playable factions:
The Order, The Rebellion, The Volatists.

Order has a stable and basic build order, not much room for variation.

Rebellion has 3 rogues as a starting units and rogues gain gold upon killing nightmares. This allows for variation in build orders, based on how many kills the starting rogues can get.

Volatists have 8 starting units worth 8 population, while other factions have 6 starting units worth 6 population. This means you start the game with 2 less population and because of it some build orders require you to kill off some of your starting units.

This build order works for any base difficulty and with hardships, as long as you do not use Heroless or Veil Bond hardships.

1. House
   
2. Woodcutter
   
3. House
   
4. Woodcutter
   
5. House
   
6. Stone quarry
   
7. House
   
8. Food hut
   
9. House (+House if Volatist faction)
   
10. Wood workshop
    
11. House
    
12. Food hut
    
13. House (if you have enough wood and food for keep after)
    
14. Upgrade the keep
    
15. Research lodge (unlock tier 2 houses)

While the Lodge (tier 2 houses) is being researched, you want to build Food huts and Woodcutters (as needed). Never build any more tier 1 houses and upgrade the already built tier 1 houses immediately.

Example video of 32+ wood build as The Order:

Example video of 32+ wood build as The Rebellion:

Example video of 32+ wood build as The Volatists:

This is a very nice build order, that is simple to use.
The hardest part is remembering to build houses as fast as you can.
Must get 33 combined wood income from 1st and 2nd woodcutters.
Must get 10 stone from the 1st Stone quarry
The Build Order:
1. House
2. House
3. Woodcutter
4. Woodcutter
5. House
6. Stone quarry
7. House
8. Wood workshop
9. House + House
10. Research lodge (unlock tier 2 houses)
11. Upgrade the keep

This is a very nice build order, that is simple to use.
The hardest part is remembering to build houses as fast as you can.
Must get 33 combined wood income from 1st and 2nd woodcutters.
Must get 10 stone from the 1st Stone quarry
The Build Order:
1. House
2. House + House
3. Woodcutter
4. Woodcutter
5. House
6. Stone quarry
7. Wood workshop
8. House
9. Research lodge (unlock tier 2 houses)
10. Upgrade the keep

To be added

Some issues you might run into, and how to solve them:

• I don't have enough wood to place the 1st stone quarry!
  You need to place the 2nd woodcutter faster, so it can be built before the wood income ticks.
  
• I don't have enough gold to place the 1st stone quarry!
  You need to place the initial 3 houses faster, so they can be built faster and add to your income. Doing it too slow costs you some gold.
  
• The build order makes me waste/overcap on resources!
  Sometimes it is unavoidable and a sacrifice must be made, don't stress over it. Also try to see if you can improve the build order yourself!
  
• I didn't have enough food to upgrade the keep!
  Make sure to get as much food as possible from the food huts you place. In some build order you just need to not build the last house if you have less than 9 food.