By default Microsoft SQL Server Management Studio 2008 R2 does not allow saving changes to table structures that requires the table to be re-created, like inserting a new column at a specific position or changing the data type of a field. The saving process is aborted with the following error dialog:
Saving changes is not permitted. The changes you have made require the following tables to be dropped and re-created. You have either made changes to a table that can’t be re-created or enabled the option Prevent saving changes that require the table to be re-created.