So I made a huge discovery that most of my repaints for ai planes don't show up in P3D V4 because they are made with bmp textures instead of DDS. I have no idea what that means really but in reading the forums people have talked about DXTbmp. They mention that this is the best program to use to convert. I downloaded the program but I see it's mostly for repainting planes and that is not what I want to do. I have not been able to find a complete manual for the program so I came here. I would just like to convert the textures so my repaints show up on the ai planes. The repainters have already done the work so I don't want to tinker with those. Has anyone used this program and if so will it provide me a way to make my repaints work?

It's quite simple really (unless I've been doing it wrong all this time...). Open the bmp file you want to convert (drag and drop onto the main windows of DXTbmp), go to Save as and choose DDS. Make sure that, when you you are asked where to save the file, to select "DXT5" as the type. From what I understand this will give you the best resolution of alpha layers, if any are included, and is typically recommended according to the P3D SDK.

Do I need to convert both textures in the texture folder. There is a l.bmp file and a T.bmp file.