I cannot speak for CFS, but IL2 has a directory called Paintschemes, that is where the BMP files go. Note that if you create your own, that the file must be in 256 colors, what results in a filesize of 1MB (for a 1024x1024 sized skin that is).
Finding out which directory is for which aircraft can be a pain in some cases.
I've written a tool that is able to open ZIP files that you download You only have to check the box of the aircraft the skin is for and it is "installed" to the proper directory without a hassle.
Unfortunately little skinners use it, but the program enables Skinners to include a readme and personal data, but more important to users: also some data what tells the program for which aircraft the skin is meant. If you open such a zip-file (like the skins I made), the program suggests these options and all you have to do is hit the install button. This is the so called automatic install option.
Here is the tool, you can view screenshots to get an idea about it's options:
http://www.simmerspaintshop.com/foru...do=file&id=129
