The thread seems to be locked up. I can't see new posts to it.
To summarize what I'm seeing, from the comments:
On the face and inner edges, some of you are using different colors along the tops and bottoms of your texture. This can cause bleed-over were a bit of the top edge smears over on the bottom, and a bit of the bottom smears over onto the top edge.
On the sides, it looks like they're using the texture you gave and smearing the colors from ALL FOUR corners together to make the side color.
If you use the same color top and bottom edges, the entire side should be that color, as well.
If you use different colors on the top and bottom, they'll smear the edges of the outer and inner side, and that smeared color will be spread over your sides.
If you use different colors at all four corners of your texture, all four colors are smeared together to make the color spread over the edges.
The attachments below are:
"You texture" four color squares.
"What SL Sees" which is the Offset (0,0) point. Notice it's a medium gray because of the colors I chose for Your Texture. Repeat (0,0) will smear that gray over the entire edge. I scaled it up to smoosh the colors together similar to what Second Life does. Notice that if you use TINY adjustments to the Offsets, you can move the color chosen just about anywhere in the texture .. into the two-colors-smeared areas, or even into the just-one-color-here area.
If you use different colors than I did, you'll get different colors.