I’ve found the reason for the exception.
There is a difference between how the adl_adGetCellList api works in 7.47.4 and 7.52.
In 7.52, adl_adGetCellList doesn’t create a list if no A&D cell ids are in use and returns an error. Hence doing anything with that list causes an exception.
In firmware 7.47.4 the function creates a list regardless and returns OK.
I haven’t managed to find any documentation on these changes. If this change is documented, where can I find it?