MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
I assume you are referring to the line / gap shown running straight through the model in the image at that link. Assuming so then yes. That is pace between the model itself and the designed in support. That gap is set at 0.30mm and will help the designed in support break away relatively easily post printing (on an accurate well set up machine with a precisely sliced file). If there was no gap the designed in support would become part of the model and near impossible to break / cut free. This gap is similar to what allows Raft to peel away from a model after printing. That has a 'raft to model' spacing applied to create a weak point which will allow the parts to separate.
I hope this makes sense and helps...