It would like to know as I make to keep my document of tests the measure that software goes growing. If changes to exist?. I must leave everything in the same document or must create a new document I contend only the changes to referenciar the document of the previous Build?. As they work with the Builds constants?.
Having the same assumption as QAGirl, I can just say is that you need to update your test documentation (no matter what kind of document it is) as soon as there's a modification done to the application under test, may it just be the colour of a menu option...
It really doesn't matter. This would be something to be decided by your company. New documentation is not required for builds or patches, but for new releases, as usually new functionality is inserted and it can also change current functionality, then new documentation is required..
We don't use a tool, but during development of documented test plans, our analysts mark changes within the document in a change management portion and number the document - this only once it's completed a full first draft. In this way, they're able to note if a particular area of test changed due to further design discussions or issues discovered during implementation.
I've also worked places that check documentation into CVS or another source management system - it all sort of depends on your environment.