So yeah, the applet is quite math intensive. I'm horrified to think how fast it would run without a JIT. Nothing much can be done about that, sans finding out new algorithms.
There are currently about 6 levels in that preview and no "game ending". It's still a work in progress, mind you.
And yeah, maybe "drag" was the wrong word, but it was the best I could think up that didn't take much space in the screen (and it gets the user to click and drag the mouse). The idea is to control the air flow. So when you click & drag the mouse, you are actually generating wind currents which the fog travels through.
Gonna keep at it.. Thanks for the feedback (and thanks onyx for the jnlp tip)!