Killer Total Tool

Screenshot
This is a version 14.0 screenshot

Killer Total Tool:

This tool is turned on and off with the Killer Total button in the toolstrip. The tool opens a panel at the bottom-right of the SuDoku Solver and provides a total of all highlighted Killer Groups.
This facilitates finding extra and missing Squares using the 45 rule. The Killer Groups are selected and de-selected using the right mouse button.
In this example, two Killer Groups have been selected which together comprise the middle-left 3x3 Box plus the Square G1. Since the Groups sum to 46 and the Box sums to 45 (the 45 rule), the Square G1 must be a 1.




Second Example of Killer Total Tool

Screenshot
This is a version 14.0 screenshot

Killer Total Tool :

In this second example, the Killer Groups selected comprise Rows F-J, with F8 missing and E9 extra. Since the four Rows must sum to 180 (4 X the 45 rule), and the selected Groups sum to 176, F8 and E9 must form a '1 In & 1 Out' with a difference of 4.