The content mapping and warping is used to correct optical influences caused by the camera, e.g. compensating pincushion distortion by using wide-angle lenses.
See here a video explaining the warping features:
The main goal is to get your calibration result neatly into your projection surface. To accomplish this, use the warping tools on the side of the ‘Final adjustments for display’ window (for more information on the warping tools go to the Warping section).
Warping is used to distort the image, so be attentive to how you mold your image into your projection surface. At this stage, you will just do a rough warping to adjust the content to your surface.
Initial content mapping
The auto-alignment will result in a single image containing the projection results from all projectors. Depending on the initial screen aspect ratio value, the projection screen is fully or partly filled with a seamless testing pattern.
IMPORTANT: During this process, look at the actual projection surface, not only at your screen.
Warp tools video tutorial