Hamanathnath

Faction: Lothlorien

Map: Doesn't matter

Pretty self explanatory, but killing the Summoned Radagast for Lothlorien will grant you experience.  I believe this is a bug because most other summons in the game award no experience points upon death.  For example, the Gandalf summon on Rivendell awards no experience.

Faction: Rohan

Map: Don't think it matters, but it was tested on Tournament Anorien

The Rohan Yeomen Archer do not shoot arrows when they bombard, unless they are equiped with Fire Arrows.

The reason for this is due to a Typo in the code.  In the "RohanArcherBowNewBombard" weapon, you will find these Projectile Nuggets:

ProjectileNugget
  ProjectileTemplateName  = ohanFactionArrowBombard
  WarheadTemplateName     = GondorArcherBowBombardWarhead
  ForbiddenUpgradeNames   = Upgrade_RohanFireArrows
 End
 ProjectileNugget
  ProjectileTemplateName  = RohanFactionFireArrowBombard
  WarheadTemplateName     = GondorArcherBowBombardFireWarhead
  RequiredUpgradeNames    = Upgrade_RohanFireArrows
 End

The "ProjectileTemplateName" without Fire Arrows is missing the R in Rohan.  Add that one letter and the bug should be fixed. 

Faction: Rohan

Map: Don't think it matters, but it was tested on Tournament Anorien

When you combine the Rohan Yeomen Archers with the Yeomen Spearmen or Westfolders, the combined Horde keeps the Yeomen Archer's old commandset.  This means that they can no longer purchase Forged Blades, and they keep the ability to switch to Skirmish Formation.  Though the formation switch doesn't seem to do anything.