<1>The upgrade from Black Khergit Horseman - Black Khergit Guard - Black Khergit Raidmaster is broken.
I did some research...
Notice that only two Hex bit is used for the ID of the troop as the upgrade 1 and upgrade 2, so the maximum ID is FF, which is 255. Currently Black Khergit Guard and Black Khergit Raidmaster has ID 262 and 261 respectively (or other numbers like that). I tried to fix this by editing the troops.txt file, moving these two troops to earlier part of the file, it works, but it also caused other strange problems.
I'll take a look at it. -HardCode
Confirmed, much thanks!! Easily fixed by moving the regular troops (Awali and advanced Khergit) up from the bottom of the troops file to just after the dark knights line of troops. Rule of thumb is regulars first, then put the NPCs and heroes. -Fisheye
<2> Probably not a bug, but...
When you refresh the troops to hire in the tavern, the two new tavernkeepers in the castle are also counted as Vaegir fraction and they will have Vaegir Peasant too.
I just did a basic copy of another tavernkeeper. I'll fix this so either no faction peasants are available, or Radoghir gets Vaegirs and Culmarr gets Swadians. -HardCode