stephendurden here with a new account :)
Result looks great. I see that huuuuuuuuge window now, I completely understand your worries :) You managed to do a very good shot, nothing to say. Bravissimo!!!
Check this video, it may help you (parts 2 and 3 are other videos. I did something like that using Trapcode Particular: it's not for free but, to me, it's the best for the particle emission work.[/url]