A lot of people seem to be asking the same question here, but none of the answers work. One guy says he has a solution but asks that you PM him. Surely this a forum where people share problems and answers?
The words "Welcome to Our Community are in a PNG file called header_image.png and NOT in promo.png. (This is the graduated blue background image for the header)
If you create your own png image to replace Welcome to Our Community, it will NOT position itself correctly. Even if it's 318 x 169, a png file at 72 DPI, it will position itself to the top left of the header. See bottom image. The center column will then force itself up into the background image.
My screenshots are the same as others presented here, but I've given comparisons.
The question is quite simple: How do you get your own wording in header_image.png to appear in the correct place?