lamni_move_to_scan_center's shift_x/shift_y are absolute offsets from the currently-configured lsamx_center/lsamy_center (unchanged until the operator confirms at the end of the procedure), not incremental deltas from wherever the stage currently sits. The extended-sample iteration loop was passing only the latest click's delta each time, so each new iteration partially undid the previous one's correction instead of adding to it. Fixed by accumulating the total shift across iterations and always applying the running total. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>