If false colours or table results are not or only partially displayed after calculation within the measuring surface, it is probably due to a bounding box of an object that crosses the measuring surface.

Bounding box of two grouped objects:


The result is not fully displayed:



Solution:
In order for the measuring area to be calculated completely, the option "Calculate measuring points inside objects" must be selected.



You will find a visual description of the solution in this tutorial.
How to calculate measuring points inside objects?