Here are a prototype version of the Acklay and Reek which was made in 2002 and later shown for the 2005 Lego Star Wars Weekend in celebration of Episode 3.
They decide to cancel this set because one of them believed "it would not sell well". I searched for any remaining photographs which I could find of the set but I have only found these three. If you have any more available please share. It could be interesting to see the Reek in closer details. Especially to see if it has anything on the tail which I have missed.
Here below are all three of the beasts together. (The mini Nexu design was made by me)
Finally here is a edited version of the Prototype Acklay which I made using the original design. As you can see it has more mobility to it's limbs, some extra details are added and finally the color is corrected.