There are two things happening here.
1. The ‘Save’ item remains grayed out after you modify the column visibility. We are aware of this, and it’s a design option that we chose intentionally for reasons that are difficult to explain in this posting. The bottom line though is that the grid data needs to be modified before the ‘Save’ item will be activated. Adding or removing a column without actually adding/modifying data in the grid will not activate the ‘Save’ item. We do not plan/expect to change this behavior. To get around this, your solution of using ‘Save as’ and then overwriting the .bps file is your best option. There is nothing wrong with doing this, and it will work properly.
2. You found a bug that prevents the ‘Disk Space (%)’ column from being automatically displayed when loading a grid that had been saved while it was visible. ‘Disk Space (%)’ is the only column where this occurs. ‘Disk Space (MB)’ and all other columns will properly be displayed when loading the .bps file if they were visible when the grid was last saved. Thank you for highlighting this bug. We will look to address the ‘Disk Space (%)’ column auto-display on load in a future build.
-Doug