To start with, you may want to revisit the beta video that covers the influence feature. This video is based on the original beta release and will be updated.
http://youtu.be/eowMUGmv2W4?t=17m55s. This will be updated with additional documentation.
Aside from using equipment, there is no actual end point of when influences are no longer applied. In a design, the affect of an influence starts at 0 and is increasingly applied based on the curve set for that influence , until you reach the number set in the 'Influence End Value' field, at that point the influence has been applied 100%, Influences are applied to the parts of the crating process that are indicated by the Slider settings. Your Slider settings allow you to apply higher or lower values which will tweak the time calculations.
A crates weight, dimensions and quantity are common factors that influence manufacturing times. An example: A small shop may have a much lower maximum crate weight they can handle before the weight affects, or influences, the time taken on that order. A heavier crate may require heavier materials so more time is spent on the saws. Or handling or moving the crate around takes longer. With the Sliders and by setting a curve each shop can uniquely set how the different factors such as crate weight, size and quantity affect their manufacturing time.
If you have kept the value of 2000 as the End Value of the Tare Weight then you are indicating the rate of change in time (not the time itself) is no longer influenced by the container weight for any container over 2000 pounds. For Crate Pro 5 users this was the Index Factors. Individually, many of the influence values in preferences have little effect when considered individually. The default settings reflect a small to mid-size crating operation and if times are not coming out as desired, you may find the times for individual inventory items and/or saw setup times to be a better starting point. Since Crate Pro's design engine has been completely redesigned, all the values should be reviewed.
If the influence values don't fit your manufacturing environment then you can create and select an equipment option to replace the desired process. Using equipment completely bypasses that part of the calculation engine. It's important to know that by bypassing the influence feature you're not using the time results that Crate Pro calculates and you are generating simple calculation results. This will cause you to be less accurate with your times and costs because you're not taking into account the variables that all shops must
These values should be set and left alone.