You could fill the platform, when it comes to small things say gears it can be handy, otherwise I just rock one part at a time. However if you want to do this, you will need to load all your models into a single file, then save it as an stl. then load it to the replicatorG programe, then build the gcode. That sounds like a lot of work but it only sounds that way. As far as support material goes, you get good at figuring it all out. Also splitting up larger parts then glueing them (or whatever you want to use) is something you can figure out for what others have done.