Incase it's relevant, even in Dev2.4 (not super-current build, but newer than 2.3.1) I've noticed sometimes shots just aren't allowed to hit aliens in certain places on certain maps. I've played enough to recognize when something's being strange, and instead of aiming directly at them when this happens (telltale signs include but aren't limited to several consecutive 99% shots from different soldiers missing at mid-range, unobstructed target) try aiming a few tiles behind them with their body "blocking" the shot.
See what happens. I'm curious.
Also about the password: yea it's damn ridiculous. I understand making it hard for spambots but it's actually hard for the real humans too now. Who won that battle?