Make sure you re-download the assets, there should be a version file in there that says V0.5; if you don't see the txt document named "VERSION" then chances are you are not running the correct version. The surprise flying was a problem I relatively quickly patched if you check the advanced support code topic.
If you want to figure out specifically what it was, it was actually the tracer projectile being stupid. Try using a sniper on someone very far away, and then after they get hit, have them step aside, then try missing and having them walk into the tracer; its pretty silly.