Is this something wrong with this expression when use in an action to retrieve the last related record?
LOOKUP(MAX(SELECT([Related childs][_RowNumber],AND(some stuff), “childs”,"_RowNumber",“child ID”)
When tested(emulator) in an action this expression returns nothing which is unexpected.
When I test the MAX() expression alone in a virtual field is works as expected returning the last related record.
When I test the LOOKUP() expression replacing the MAX expression by a number I get the related record.