A couple of things i see right off. The wood does not register as wood in your texture. It looks as though you just used a procedural material or flat color for the red. Considering it is wood, there is no real bright red wood colors. Second thing is there are no highlights or shadows etc on your lock and chest. They look…
there's a reason they've given you two sets of concept art - they want to see that you can translate the specific design of the tree sketch through to the colourful lego style shown in the fungus sketches and i don't think you have. First off you've lost some of the specific details in the tree - the curls on the hanging…