Report any problems in the wiki here and any vandalism here.
To modify the look of the Oasis (default) site skin, go here.
If you need help with anything feel free to leave a message on an administrator's talk page (with the most recently active administrator's talk page being located here). You should sign your messages on talk pages using four tildes (~~~~). This will display your name and the time you put it there, so we know who needs help.
If you just wanted a larger version of the original flag, with the bottom stripe blue, you can get almost any size of it that you want just by going to this link and changing the number at the end of the URL (ie., '3000') to the width in pixels that you want the flag. I made a similarly-scalable version of your variant, which you can access (and download at whatever size you want using the same method) at this link.