Game keeps freezing when trying to destroy unfinished Emancipation Gate

[Selereth]

My game keeps freezing up when I try to destroy Brasilia's Emancipation gate, which mind you hasn't been finished. I managed to destroy it once but he started to rebuild it, and I wanted to get rid of it a second time before it became active, but everytime I select a unit and right click on it to destroy it, my game completely locks up, I can move my mouse cursor and the sound keeps playing but I can't press any buttons or exit the game, I have to press the power button to get my computer to close the game.

Is this some sort of major bug (i.e. has anyone else run into this sort of problem) or is it just a "me" thing? I guess the workaround would be to try to win before he does?