A compatibility thing, In Vavoom if the player is on a floor which is at height=0, the projectiles (rockets, plasma, BFG shots) shot by the player will now hit and stop to a floor step which is at height=32. This is when the player's view is centered and there's nothing shootable at sight. But in vanilla Doom the projectiles fly over the floor steps at height 32. But they stop to a floor step which is at height 33. Projectiles shot by monsters seem to flow fine, thought. I was hit this issue when playing icarus.wad map30 and the rockets exploded to my face... <!-- m --><a class="postlink" href="http://www.doomworld.com/idgames/index.php?id=5191">http://www.doomworld.com/idgames/index.php?id=5191</a><!-- m --> Here's also a test map. (Try shooting projectiles over the steps.)

Fixed.