Certain tools generate a sequential list of commands to change the model.
Those changes are held in this 'changes' list and simulated visually until you are ready to execute the changes into the real model. Note -Some commands have no visual feedback.
You can use the up arrow button to move up in the list. (All commands above the cursor are generated, and those below the cursor are ignored) The down arrow button will add those commands again. Note - when the tool Execute button is pressed, all the commands in the list will be executed, even if the cursor is not at the bottom.
Use the delete button to delete the previous command from the list.
Use the Insert button to undo previous deletes. Note - you can use this option to reorder commands by inserting from a different place in the list.
Once the tool is executed, the batch list is cleared and can no longer be executed.