This feature is already in place with a bit more flexibility than a full lock of a field. Understanding when Crate Pro makes changes will help you get the most speed out of your design creation. Locking a field would mean that no changes would be allowed. If you change the crate dimensions or the materials being used which would then require changes to surrounding dimensions, locked fields would not recalculate to account for the changes. Locking can not be partial.
Your changes to field formulas are retained upon duplication and when creating a new design from a template. Users can Run Rules on the entire design or on a panel by panel basis to recalculate the material dimensions which gives you the flexibility to recalculate what components and panels needed. This applies to Build 3045 and higher.
I didn't complete the answer - Let me add a little more information.
What is difference between Template versus creating a Stock design?
They are similar but depending on the company have different uses.
When you create a template a user is unable to select the template directly for addition to a Project. When user select to create a new design from a template a new design will be generated with its own design number and any changes will not affect the template.This preserves the intended modifications in that template.
Duplicating a design also creates a copy and allows you the ability to make changes to that design without affecting the original, however, what commonly occurs is that a user doesn't duplicate the design and make changes on the duplicate, but simply opens the original and make changes there. The modifications on the original design are lost.
Companies can decide individually if creating stock designs is easier or the security if creating a template is a better option. Of course you can do both.
I am very happy with this software but I do use Templates and Duplicates of previously edited formulas of crates to make it work for certain designs so that material is used at the highest yield.
If we had the ability to lock an edited formulas that we have added in a template or duplicate so that we could run rules after adjusting the length, width or height.
Currently if I say have a template with edits in fields such as sheathing and it is 48 x 48 x 48 and I want to change to 48x24x46 it reverts back to the default formulas.
This would be a very beneficial feature for anyone who uses templates or duplicates.