If you want to add the ads to Biohazard, first thing you would want to do is get Biohazard into the botlab and export the texture.Then you would want to open it in GIMP/Paint.net and resize to either 512x512 or 1024x1024 (I use 1024x1024 myself).When saving make it a 24 bit bitmap.If you want to make a new decal, use the GIMP/Paint.net and make a new file at 128x128. delete the white background and place whatever you want there, they save it as a 24 bit bitmap in the decals part of your texture library.
You actually don't have to touch the bot file to make a custom texture, here's what you need to do:Within the botlab, you go to the paint shop tab, and there's a button "Export Custom Texture" or something. You click that, and give it a name. Then quit or alt-tab out of the game, go to your RA2 folder, and the paintjob will be in the Custom Textures folder. It's a 256 x 256 BMP, each of the green shapes is one panel, and only things inside the lines will show up on your bot. You can resize it by any multiple of 200% and it will still work, in fact I recommend stretching it to 400% if you want it to look good.When you're done drawing on it, go back to the paint shop, and do "Import Custom Texture." If you've done everything right, it should be there