Thank you for this. This is one thing that should be corrected. For now we put the id hard. We plan to change this in a way that the user will set it in a way what they want. Maybe will be available in the next release.
Your beforeSubmit handler can delete the postdata.id field, and add postdata.row_id.
You need to be careful handling the “add” case (rather than edit), because the grid differentiates the two by checking whether postdata.id == “_empty”.
You can solve that by /not/ deleting the “id” field (in which case the server will see both id, and row_id), or by adding it back in your afterSubmit function.
Mark, I ended up changing both the language column names by adding a prefix and changing the id input parameter to row_id as soon as the execution enters the server code.