Locking seating plans

I arranged a seating plan for my class but when I next opened IDOCEO, the students had reverted back to alphabetical order. How do I lock each of the five plans? Thank you in advance.

Hi kazzm,
The seating plans should keep its position by default as there is no option to lock its.
Give this a try, do a couple of changes in the seating plan, then go to the grade book and back to the seating plan. You should see the plan in same position, let me know if not.
If you can provide some steps on how to reproduce the issue we'll keep an eye on it