What do the red and blue dots next to your units in the left-hand column along the edge of the screen mean?
They're the buildings. Red indicates one under construction, blue is built. Not quite sure why it's necessary tbh.
Oh, and a couple more FAQ's:
1. Why can't I talk to an NPC?
If you see a speech bubble with a red line through it the usual cause is that they're either out of your influence and you have no units adjacent, or you don't have enough gildar on hand to recruit them. You can check by selecting the NPC, going to the action tab and hovering over the greyed out handshake icon. The tooltip will tell you why you can't communicate
2. How do I equip my heroes?
You can access a store from anywhere within your influence (the area within the borders on the map) which allows you to purchase any equipment you have the tech researched for (and it ignores resource requirements). You can also find equipment as loot, as a quest reward or from the goodie huts. To equip a character, select them (so their portrait is in the centre bottom of the screen) and click the shield icon on the right. This will bring up the equipment window showing you what they're carrying; items in a coloured block are currently equipped.
You can also trade between NPC's in the same tile by going into their action tab and clicking the trade icon (the scales). This brings up a window allowing you to move items between the units in the square
3. How do I level up a town? / Why won't my town level up (minors)
The level of a settlement depends on it's population. If you select a settlement you will see a bar in the bottom left with a house icon in it. This shows you the current population and the limit from the current housing in the town. Hovering over it will give you the exact numbers.
Minors (the one town empires) will never level up no matter how much housing you build. The only benefit to conquering their cities is that they usually have a key resource nearby to exploit, particularly the non-human recruit locations.
4. How do I recruit ships/spiders/etc
Once you have the relevant building click on the associated town and you should see the unit available in the train menu. Only towns who have a necessary site linked can build these units, and you can't design them.
5. What are caravans for?
Caravans allow you to trade between your own settlements, which generates extra gildar and food. To use, simply train a caravan at one town and move it to another - a road will form and traders will begin to move along it. Selecting one of these traders will show you what they are boosting in their unit info. Note caravans can be destroyed if these traders are ambushed, the road however stays.
6. My sovereign ages far slower than their children
Your sovereign has the benefit of magic running through their veins which allows them to prolong their life. It also means you get to use your children as heroes within a reasonable time frame.
7. Can I raze cities?
Yes, but only once you've researched the necessary technology (it's in the warfare tree on the siege branch)
8. How does this tech thing work anyway?
Rather than research specific techs, you research into a single school. Once you have accumulated enough research points for a breakthrough you may then select a technology which is immediately unlocked. When you select a school on the tech window you can see the potential technologies you will have to choose from in the pane next to the description, as well as the likelihood that you will be offered them with your next breakthrough.