Reality Factory

I was wondering how you make invisible models for triggers.

It might be a little late but I could help with level design. Also I could help model some guns.(I don't know how to export and animate them ect... but i can still model them)

Thank you for the help.

I'm new to Reality Factory. I've read a few tutorials and am in the process of making a game. But I would like to know how to make it so when you character goes to a certin point it goes to a different level? Is that possiable?