You definately get points for originality, but the seams in your rockwork show badly.

OK I had a go on this level. To be honest, I really liked it. It needs alot of work, but I think you have the basis of a good level.

Firstly you need to understand- you don't need to do crappy trees with brushes anymore, there are model trees which look really good. At the top of the waterfall you should use loads of model trees. You'll find only 4 of the tree models have green leaves as skin number 3 (oak_tree01.mdl, tree_deciduous_01a.mdl and 02a.mdl and tree_poplar_01.mdl). Use these loads and also learn about the repeating grass sprites that appear on certain grounds.

Also- niggly problems I found:

You don't seem to know what or how to use cubemaps. You need on on your water surfaces to make the reflections the right colour. Your rope bridge is a bit iffy- the slats that you walk on are hovering. Your waterfall texture is really crap and has a crappy scroll to it, all flickery. Your dustpuffs you've use to make the waterfall spray need work. Theres a few wierd random cravaces that look a bit wierd, you need to line up and make that skybox a bit more complex to make them look better. Use the distant tree models (the tree line, I know they are all dead trees but it will look better) for the skybox.

The main issues with this map summed up=

You need to do more displacement on your rocks. Use the Noise subcommand on displacement to make them a bit more jagged.

You need to sort out them ropes, they really are crappy.

You need to sort out your foliage and niggly problems.

You need to make the lighting better. I suggest making it day time and bright so to get more contrast in the map. Maybe make the fog a bit more severe too.