X, Y, Z Mapping Factor: Controls how far, as a percentage, selected points are moved along each axis towards the "virtual sphere" surrounding them.
OK: Closes the tool, with alterations intact..
Cancel: Closes the tool, canceling any alterations.
Set: Makes any alterations permanent, and leaves the tool open, ready for further use.
The DoBeSphere tool also includes a standard Origin Tab, allowing you to set the Origin around which the tool conforms points.