Great feature, I've had to manually assign alot of grid IDs in the past!
I noticed something last night when testing v527.
When duplicating grids that have numbering higher than '99', they are sorted alphabetically, instead of numerically.
But the new Batch Assign feature (v527) was 'smart' enough to understand.
With the v528 the IDs are just assigned in order. See attached pics.
Also, the Batch Assigned IDs always start at '01' even if I input '1' or '001'.