I can't think of any real easy way to explain this, so I'll attach some images to help me, but basically what I did is take the curve theme from 2.0 RC5 and modified the main_block.png, backdrop.png, and frame_repeat.png in order to change the color of my forum. I also edited the index.css file to change the background color.
My problem is that on some of the headers, while my new color shows up, a small part on the left side is still the color of the default curve theme. I can't for the life of me figure out why it is doing this or how to correct it. If I swap the image files for the ones existing in the default theme folder this doesn't happen, but if I make a copy of the default theme and modify that it does.
Also, it appears to only be affecting the headings associated with my simple portal blocks.
you are using simpleportal? if so copy your portal.css file to your css folder for the theme you are using
Oh you rock, that was exactly it, thanks so much.