There's a bug in Interactive Grid in case you have filter over it and add new rows that don't meet the filter criteria ( tested on apex.oracle.com, version 5.1.1.00.08).
You can reproduce it if you have department filter over employees IG and you select Accounting department as a filter and add employee to another department (for example Operations).
Demo is available here: https://apex.oracle.com/pls/apex/f?p=apexbyg:30
Of course, this is simplified example and yes I know I could restrict department select list in grid only to filtered department or remove it from grid...
@"John Snyders-Oracle" please help, at least for next APEX patch/version!
Br,
Marko