lol the rules kinda seem to be changing on the colours if using palette or not..So best advice to people making stuff is:
You have like lot more chance of getting your stuff ingame if you just use the palette colours (most of the items etc ongame use it!)
So I'd suggest you just use it(exact colour not shade of -thats different colour) reason they have palette is so pretty much everything has same sceme all the way through the game giving it more of a professional finish and makes look alot cleaner.