TMA - Range Rate and Target Zig

Hello everyone, I have a question on the Range Rate TMA I hope some expert can answer:

I can not see that link there is between the range rate and the representation of the difference of Bearings in a Target zig.Nel manual written by TMA TopTorp explains how to calculate the rate range but do not understand how to use it to understand a Target Zig.
How to determine which side has turned the Target Range by calculating the rate itself varies even if the target does not zig?

Thanks,
cristian