First "bug" playing on the Pelargir map in the fortress defense slot using Rhoan, Rivendell or MM you can have builders or recruit them.
Second bug, in the dead marshes in the Southwest slot, the base is on the water.
Last bug, I don't remember the map, but playing with lothlorien if you use the ability of the Sinar Pathstalkers and an enemy uses Blessing of Manwë / Western winds at the same time, the Sindar will be permanently blocked, they cannot move and are in a state of stealth (therefore the enemies cannot kill them).