Extracted from the wbc3 wiki: http://etheria.wikia.com/wiki/Bugs
1. A building's range is misleading, as the range starts from the center of the building, but yet the edge of the building is what enemy targets can hit, essentially meaning the building has a lower range than what it says. This also means a ranged unit with equal or even lower range than a tower will out range it. FIXED
2. Due to the way that building upgrades to other buildings work, the Plaguelords' Fire and Ice caves do not use their own sound files when they were built as an addon to the Hydra Cave, but instead use the Plague Shrine's sound files. A pre-place Ice / Fire cave uses its sounds correctly, though, as it was never built upon another building. FIXED
3. When a building during construction is destroyed, it will first display it being fully built before it collapses. FIXED
4. If a building is destroyed just beyond your screen's edge, then the building wont fall down - still counting as being there for the purpose of a side's AI targeting and for "stop defeat". Scrolling the screen over it causes it to the fall down like it should have done. FIXED
5. The game does not check build requirements based on other buildings before placing the building down to be built. This allows a builder to build things that it should no longer be able to build. FIXED
6. Units that can't build from the walls/towers tab can still build such buildings by first selecting a wall/tower to build from a unit that can build these and then have the player press the "next idle builder" button to cycle through to the builder that normally cannot build that building. Choosing to place down the building now causes that unit to build that building. FIXED
7. The Mortar's firing position for its projectile is incorrect and results in the projectile being fire from "nothing" to the right of the Mortar. This looks like the .bui file was never updated in this regard when the new model was made for it for WBC3, as the WBC2 model was longer horizontally and the projectile was launched from the right of the center of the building. FIXED
8. Buildings have a missile-resistance to Flaming Poison Arrows, but not normal Flaming Arrows. Regardless of whether it inflicts poison or not, they're both flaming arrows and to a building would be equally effective. One of them is wrong. FIXED
9. Despite buildings being resistant to all physical missiles, they have no special resistance to rock projectiles (the ones that Trolls have). But is this one actually meant to be an exception? N/A - buildings are vulnerable to crushing damage
10. Spider Eggs, Wall of Ice and Wall of Thorns all set on fire when damaged. Due to the combination of low hit points or and material type, I believe these buildings shouldn't set on fire when damaged, just like the Gravestone. FIXED