Here's a bug report for you: I downloaded it on a friend's machine (WinXP, 1.8GHz Athlon, GeForce 4MX) and it worked fine, but he hated it. Can you add a multiplayer mode, convert it to first person, set it in a maze of rooms, provide different weapons and call it Quake 4 please?
More seriously though, a Mad Jelly launched a ball of plasma at me at some point which didn't move anywhere. It sat there on the spot flaming madly, and survived me dying, going back to the menu and starting a new game. It still sat there, flaming at me. I didn't run into it, so I don't know if it were "live".
Without any log or anything, there's probably not a lot you can do about tracking the bug down - probably easier to just clear all active battle zone features before starting a level or something?
I have no idea what caused it, and my only thought is that maybe I spawned in on top of a Jelly just as it fired, and it gave the shot a zero-length velocity vector?