Glad to help
I struggled with that for like 3 days, reading different forums, trying to ask in chat rooms, etc. Another forum member ihtfp69
showed me one of his that used JPGs and yea, that made life so much easier. 13MB is still a pretty hefty sized boot animation since it gets stored in your internal phone memory. If you use a2sd it's probably not too big of an issue, but if you are wanting to share with the community then it might be something to look into as that might scare a few of them away. Check out my Mario one in this forum, I think it's pretty cool too
I have a Wall-e and Eve one that I did for a forum member over at android forums but not quite sure if it is polished yet, waiting to see how it works for him. Anyway, have a good one!