Well, I finished RC3, and 14 days before the deadline no less!
Here's a full list of the changes
+Added tree skycards in the skybox
::Adds more realism as well as hides some skybox seams
-Replaced the wood plank fence in the flank
::The fence was changed into a func_detail brush
-Replaced the stack of logs on BLU flank
::Replaced by a porch as well as some toxic barrels
-Removed some silent ambient_generics around the map
+Moved back some floating trees of the cliff
+Did a clipping pass to reassure no clipping exploits
+Added 2 more train cars behind the main engine
::Right behind the train is a gravel car and a rocket car