It sounds like you are trying to manually modify the G-code to start from a specific layer. To resolve the "extrude only move too long" error, you can try adjusting the feed rate or extrusion distance in the relevant G1 command. It's possible that the extrusion amount set in the G-code is too high for the movement being made. Try lowering the extrusion amount or adjusting the feed rate to ensure smoother extrusion during the move. Test the modified G-code on a small section to ensure it works properly before proceeding with the entire print.
acoustic reef
fallen stag