[F22-Raptor-2006]

Well most people use this thing called "Bright" it converts your 3mb BMP files to 1mb without loosing any colour in any way. Bright can come in a folder where you just click a batch file that will automatically change the bmp files in the bright folder to 1mb standard which will work for il2. Personally I have it as a plugin on photoshop and just export skins already done to 1mb. I don't remember how many bit a 3mb file is but u just save it as that and then do the bright thing.