I strongly suggest the new cura slicer software from http://reprap.org/wiki/Cura compared to what is included with Repetior host. Also check out netfabb.com for dividing up a 3d print to fit on the printing bed.
Just passing along, I am not affiliated with either one.
Scott
Slicing software
Re: Slicing software
What are your settings for the Geeetech Prisa i3 B?