Qube out-of-the-box does not handle tile rendering of a single frame in XSI.
One can manually tile regions of an image using the "XSI BatchRender" by setting the Image Resolution->subregion parameter, though this will be a manual process and will also involve manually stitching the images together.
Note that Qube does support MentalRay Satellite Rendering for Maya and 3dsMax that does have this capability for single-frame tile rendering across multiple machines.
Most all of our features are customer driven. Up to this point we have not received customer feedback to indicate that there is a strong desire for this functionality. If there is, then we can reassess that feature request.
