I have master (for e.g. dept), details (for e.g. employees) IGs. In master, I have disabled multi-select so it rendered as radio button.
Now, If I select department-A, and then add/modify employees in details IG and click on custom "Save" button (page level button created by me, it submits the page), then after page reload, "selection" in master IG is not preserved. I think, this can be achieved in two steps