You can run the box model by clicking here 
I'm still working out a few issues as far as time steps, and concentrations, so be mindful that your emissions and concentrations are within reasonable ranges of each other; that your box size is large enough; that your wind speed isn't too large; and that your timestep stays small (around 1 second). The more days you run it for, the longer it takes--I recommend starting with a few days first.