ya GIMP is awesome once you figure it out, its not that hard....
first thing to do is down load your default skin...no thats wrong
create a new folder in your AH skins folder name it the name of plane example p40e_1
go in game save the planes default skin
that will create a folder for that plane go into that folder and copy the bmp file that you want to skin
paste it into the folder you created then open GIMP and point to that file to be opened the one you pasted into.
you need to change the file to RGB to edit it, to do that go to "image" and then "mode" and then at the top will be "RGB" when you are done editing it you need to put in back to indexed.
yup "window" and go to "dockable dialog" a window opens and choose "layers"
create a new layer, the layer window may be open if not go into the top tab named "window" i believe... hold on...yes A new layer window will open with a small thumbnail, move over that thumbnail then right click create new layer, it will be same size 1024-1024 (this is the size it needs to be) make it all grey, light grey turn down the opacity, so you can see the layer below, from there trace out panel lines... thatll keep ya busy
