Hi Niel, the problem with slings is that they don't quite have the coloration's they have when slightly bigger. It's also very risky to identify T's on just their looks and colors. That said, lets see what I am quite sure of :
1. Wouldn't guess at this stage
2.Brachypelma smithi, (Mexican redknee) The whole knee is light orange/red, where as the flameknee (Brachypelma auratum) would have a distinct red (flame) in the lighter color only on the extremity of the knee. Then again, it hasn't developed the coloration of an adult yet.
3.Brachypelma vagans. still small and should darken up on next few molts.
4.Looks like a Grammstola pulchrypes to me too ( Chaco golden knee)
5. Brachypelma vagans again. The light carapace, dark legs which are grey from the knee down. Will turm nice and black with next molt.
6. This is the hardest one, I'm thinking Lasiodora klugi ( Bahia scarlet birdeater )
Let's see what the other forum members think.