New roofs looking funky

[pinketamine]

I have made some roof recolors. The problem is that, even when the under and the edge parts have the exact same color than the roof itself, the roof ends looking darker ingame for some odd reason. I still have the textures, so if I need to make any modification I will easily be able.
Here you have some pictures so you can see what I'm talking about:
http://i873.photobucket.com/albums/ab298/pinketamine/Sims%20-%20WIP/pink.png
http://i873.photobucket.com/albums/ab298/pinketamine/Sims%20-%20WIP/lightgreen.png
http://i873.photobucket.com/albums/ab298/pinketamine/Sims%20-%20WIP/lightblue.png
I have made some darker colors, but it is more noticeable in these, which were supposed to be almost neon looking.

I have used DXT1 format for the roof. I have thought about changing it to DXT3 and see if there is any change, but it does not really make sense.
I haven't bump-map, because I don't like to use it in any thing I create.

Does anyone know why does this happen and if there is any way to make the roof look how it should?

Thanks so much, any help will be really appreciated.

[lucy kemnitzer]

I can't see the pictures, but I have had a similar experience, just with the edges and not the under part (which comes out a bit darker than I intended but not a lot). Changing the DXT format didn't change the situation. What I think is that the answer is in the material somewhere, but my understanding of materials is so vague that I don't even know what to look at.

I was really disappointed with the edges. I tried putting a pattern on the edges so it could look like some of the "victorians" around here but the distortion was irredeemable. But the underside was pretty responsive.