Error while running event mining-patch-planner::on_player_cursor_stack_changed (ID 31)
Unknown sprite "entity/anfilts-butil-itemless-ultra-belt"
stack traceback:
[C]: in function 'add'
mining-patch-planner/gui.lua:157: in function 'create_setting_selector'
mining-patch-planner/gui.lua:586: in function 'update_belt_selection'
mining-patch-planner/gui.lua:1022: in function 'update_selections'
mining-patch-planner/gui.lua:1042: in function 'show_interface'
mining-patch-planner/control.lua:213: in function <mining-patch-planner/control.lua:195>

Thanks for the report, released an update that fixes it.