Thanks heaps, Rosemaryr - unfortunately, despite your awesome help, I'm still retarded 

I tried ungrouping the imported ivy, but nothing happened and when I tried to assign the materials to it, it would only take one, thus making it look really silly.

Am I importing it with the wrong settings? Attached is the screen that comes up when importing.

Should I just get a trial version of Bryce and import everything there? Is it easier that way?

Also, Agent Smith - what lights did you use in your scene? It looks gorgeous!

Thanks heaps guys!