Heyas... I could be wrong... but sometimes some answer is better than no answer. However, sometimes it may be more harmful than just keeping quiet. Let's see which applies here... heheh...
I'm somewhat relatively new to vBulletin as well. I used it years ago but left the license with my ex and started up new forums using phpnuke. It's good to be home again... but I'm having to relearn vBulletin. The folks here have been quite helpful... and are a damnsight more friendly than the ones over at various phpnuke forums. I guess you get what you pay for huh?
If I remember correctly, even tho you modified the code yourself instead of downloading it, it may still be considered a modification. The techies here can help you when it relates specifically to the code they developed... but once you start manipulating it yourself, you'd probably be better asking questions about what you're doing in a forum related to mods.
Hope that helps.