Unit Design Help Please.

I am using Gimp to design units is there a way to do it so this likke pink coloration will go away. And is there a way to do it without losing clarity.

Here's the thread to see the unit pics

http://forums.civfanatics.com/showthread.php?t=125307

You can't tell from the unit pic but in gameplay theres this pink coloration at the bottom of the ship. How to I get rid of it?

You really should be asking the guys in the Scenario Creation Forum:

http://forums.civfanatics.com/forumdisplay.php?f=14