Fuel is by far your best one yet. I really like the style of it. I left some suggestions for the latest ones. I hope I was not too hard.
The biggest complaint I have is you need to create your own backgrounds for midi, explorer and dialog windows instead of using the default. The best/worst advice I recieved was from Alexandrie when I asked if I could borrow

some buttons; "Make all your own bitmaps for everything, it is alot more work but you will get more satisfaction from it."
I would work also on the positioning of things. It is a pain in the ass to do (tweak, reload, repeat... over and over and over.....>

) but I think it makes a differance.
Your skins are getting better with each one. Keep at it.