If the only file you changed is the rain.png, that's all you need to include in the texture pack. When Minecraft doesn't find a certain texture, it just loads the default one.

Can't wait to TROLL!

Even though I'd probably have to wait till summer for my friend to come over. :/

Honestly, this could be made really quickly. The rain isn't even .05% of the pack, it is a really small part. You cannot classify something as small as the rain as a full blown texture pack. And pluss, all the crude upside down faces falling on you house would get really annoying, really fast. Now, before you go off saying that I'm being mean, or that if I don't like it I shouldn't say anything, know this: Hate is better than positive comments. It lets you know that you did something wrong, and what you can do next time to fix that and keep the hate away.

Have a nice day.

:D

not bad for a first one it looks really great well the rain :P keep at it and you might get a very very succeful pack publiched to an important minecraft website :)

That's cool. Keep at making texture packs. :)