Infact that foliage goes equal with landscaping i woudl suggest to take a look on this one:
http://rctlounge.com/forums/showthread.php?t=1111
So you learn the basics which trees/shrubs should be placed where if you wanted to go for an realistic look. A thing that alot of people do wrong in RCT3.
They place different trees near each other, that would be never happen in real.
With Meercat's basic landscape tutorial you learn it, how it could be.
With the basics you can practice the rest itself. There isn't any rule for placing rocks/shrubs/flowers and so on. And with enough practice you'll find out, on which places it looks good, and where not.
You also can use real pictures with an really close foliage that you want to have on your coaster to become a feeling how it should be, what types of trees/shrubs/flowers are used in real.
With this info's you can rebuild it in RCT3, doesn't matter if some pieces aren't right.
But big faults like:
- Palmtrees besides Pinetrees
- green leaftrees (spring/summer) besides yellow/orange leaftress (autumn)
should be avoided
Soo long, Cobra
Edit:
About your CS problem, i use n7's Ornamental shrubs and others, too.
And everything works well.
Check out the folder/file:
"n7 Ornamental Shrubs" should be the name in the themed folder, after unpacking you have two folders with "N7OS".
You see, they work fine and without any problems ingame.
Re-download it and try it again. Somewhere along the download/unpack/install way you did something wrong.