WOOOOOOT! I ordered a tenergy battery for half the price of the ultrafire protected cell I bought earlier and now it works flawlessly. It must've just been a crap battery, or maybe the protection was kicking in or something. Who knows. All I know is now I've got a functioning 1.4W laser, and I'm not buying ultrafire anymore.
Thanks for all your help anyway, guys.
Thanks for all your help anyway, guys.