You can resolve the issue where the Child Data Allowed box doesn’t stay ticked in the Mosaic Information Viewer (MIV) configuration, by following these steps:
In Mosaic, go to Config Tools.
Click Tools.
Select Interfaces.
Select Mosaic Information Viewer (MIV) configuration.
On the Partner Systems screen:
Tick the Child data allowed box.
Untick any one of the Allowed roles.
Re-tick the Allowed roles, ensuring the default role is also re-selected.
Click Apply and close. (See screenshot)
You should now see that the Child Data Allowed box stays ticked.
If the issue keeps happening, please raise a new case with the Mosaic Support team, mentioning the issue and this article.