I'm adjusting my request after setting it with the player request crafting layout mod, and it ends up creating LOTS of empty rows as I delete the useless requests.
Is it possible to add a function to delete empty rows and move all of the below objects up, and possibly add new empty rows?

Yes, i will probably release a new version tomorrow, which will at least have commands to remove all empty rows and insert empty rows. I'm still testing those functions and might add another one to remove all empty slots.

The latest version has two new commands:
/at_compress to remove empty rows
/at_insert_row to insert an empty row, e.g. to insert after row 2: /at_insert_row 2

nice. thanks