Problem Solved, see #7
Inspired by the "TMO_Sample_emblem" mod, I want to add the hull number to the subs, just like the pic below (from OTC 1.5 LoadingScreen).
Then I tried to edit the *.dat file to add 2 planes to the bow of a sub (taking Balao class as an example) and added an *.tga for them as the hull number.
I just exported the *.obj from the conning tower and imported it to hull.
When i finished that, The emblem is right, and i can see the hull number in the bow. Everything goes fine except for the "red color is missing" issue of hull number. It should be white, but now it looks like green and blue. (if you use photoshop to open this tga file and disable red Channel, you will get the same result.)
Besides, if i don't enable the "TMO_Sample_emblem" mod, there will be a blue-green square on the bow, where there is suggested to be nothing.
It's my first time to use S3D, i'm not quite familiar with the mechanism.
Could anyone help me and tell me what's wrong with it? Thanks in advance.