Re: How to freeze a verson from change in master data
read after that your main concern is the list of employees and I agree with you. My advice is not to try to maintain the list of employees valid for budget. Your list should be live for your forecast etc. Make a copy of the budget list into a new list of just keep it as a reference. You could base the calcs on it as well but it's going to be a bit complex.
Option 1: Make use of Bulk Copy Functionality under Version Settings. Create a Version called "Frozen Budget", use Bulk Copy Functionality and snapshot the data from Existing Budget Versions to Frozen Budget Version. Note: This is an admin activity and cannot be published on to the dashboard. Also Adding version will have an impact on the overall size of the model
Option 2: You can use DCA on the modules along with Formula Scope but this requires a considerable amount of effort. I would keep that as my last option.