I think you've used semitrasparency; that's not allowed in PixelJoint... Anyway I think that's not necessary and somehow quite disturbing, so you should think about changing it.
As for this and others of your characters, they are nice, but really way too small. Barely someone can understand the picture... Maybe you could make a 3x version...
I'm sorry I'm just a bit confused, what is semitransparency? I'm pretty sure the background to these several guys are 100% transparent..