how difficult is it using sketchup to create your own CS? i am thinking it would be much easier for me to build a structure in that instead of trying to use different sets to make a structure in game.

I have tried a couple of times to make my own cs. But I found it to be a challenge. I am not sure how old this is but here are some of the tools you would need (if you don't already have them):
Sketchup - Blender
Importer 16, 17, or 18 (I think the latest one is importer 18)
There are modeling plugins you will need to install to use with sketch up.
http://coasterfreak.wix.com/rct3customsc...tools-page
DasMatze also has some helpful tools:
http://www.customscenerydepot.com/index....;down=1677
If you could figure out a way to get in contact with Station Jim Jr. he is one of the master's (in my opinion) with creating custom scenery. He is always uploading work on the custom scenery depot website http://www.customscenerydepot.com/
I have not found many tutorials on youtube on how to do this.
If you are able to find any easier way to do this, please let me know.
Thanks.