diff --git a/cpdctrl_gui/ui/main_window.py b/cpdctrl_gui/ui/main_window.py
index b84aa79..2116a71 100644
--- a/cpdctrl_gui/ui/main_window.py
+++ b/cpdctrl_gui/ui/main_window.py
@@ -278,12 +278,12 @@ class MainWindow(QMainWindow):
 
         log.info(f"Starting measurement with:\n\tinterval = {interval}\n\tflush_after = {flush_after}\n\tuse_buffer = {use_buffer}\n\tmax_measurements = {max_measurements}\n\tstop_on_script_end = {stop_on_script_end}")
 
-        # the time left estimation might be a little to short, since the actual measurement is started a few lines of
-        # code later
-        t_now = time.time()
-        self.w_led_script.w_time_left.set_start_end_time(t_now, t_now + led_script.script["dtsum"][-1])
+        # have the led script member be the only auto-updating script,
+        # and pass a non-updating copy to the measurement thread
+        if self.led_script is None:
+            self.led_script_load()
+        led_script_no_update = self.led_script.copy()
 
-        self.led_script = LedScript(script=script, auto_update=True, verbose=True)
         self.data_collector = DataCollector(metadata=metadata, data_path=AppConfig.MAIN_CFG.get("dir_cache"), data_name=name)
         # data_collector.clear()
         self.data_queue = mp.Queue()
@@ -292,7 +292,7 @@ class MainWindow(QMainWindow):
         self.proc_measure = mt.Thread(target=measure, args=(
             self.vmdev,
             self.leddev,
-            self.led_script,
+            led_script_no_update,
             self.data_collector,
             interval,
             flush_after,
@@ -309,25 +309,31 @@ class MainWindow(QMainWindow):
         self.measurement_timer.timeout.connect(self.measure_update)
         self.measurement_timer.start(300)  # TODO: set interval
 
+        # the time left estimation might be a little to short, since the actual measurement is started a few lines of
+        # code later
+        self.led_script.start()
+        self.w_led_script.update_time_predictions()
+
     def measure_stop(self):
         log.info("Stopping measurement")
         if not self.measurement_is_running():
             raise RuntimeError("measure_stop: Measurement is not running")
+        self.set_status("Stopping measurement")
         self.command_queue.put("stop")
         self.measurement_timer.stop()
         self.proc_measure.join()
-        self.set_status("Ready")
-        self.led_script.stop_updating()  # stop watching for file updates (if enabled)
+        self.set_status("Saving data...")
         self.data_collector.save_csv(verbose=True)
-        data, metadata = self.data_collector.get_data()
         self.proc_measure = None
-        self.led_script = None
+        # dont update w_led_script, keep displaying the last values
+        self.led_script.reset()
         self.topbar.enable_button("meas_start")
         self.topbar.enable_button("connect_vmdev")
         self.topbar.enable_button("connect_leddev")
         self.topbar.enable_button("meas_save")
         self.topbar.enable_button("meas_load")
         self.topbar.disable_button("meas_stop")
+        self.set_status("Ready")
 
     def measure_update(self):
         import time
@@ -368,12 +374,12 @@ class MainWindow(QMainWindow):
         if self.measurement_is_running():
             QMessageBox.critical(self, "Measurement running", "Can not load data while measurement is running")
             return
-
-
         if os.path.isfile(filepath):
             data, mdata = DataCollector.load_data_from_csv(filepath)
+        elif os.path.isdir(filepath):
+            data, mdata = DataCollector.load_data_from_dir(filepath)
         else:
-            raise FileNotFoundError(f"No such file or directory {filepath} not found")
+            raise FileNotFoundError(f"No such file or directory: '{filepath}'")
         self.w_plot.set_data(data[:,1], data[:,2], data[:,3])
 
     def measurement_load_dialog(self):
@@ -394,12 +400,20 @@ class MainWindow(QMainWindow):
     def led_script_load(self):
         script = self.w_measurement_settings.get_value("led_script")
         try:
-            self.led_script = LedScript(script=script, auto_update=True, verbose=True)
+            self.led_script = LedScript(script=script, auto_update=AppConfig.MAIN_CFG.get_or("led_script_watch_file", False), verbose=True)
         except ValueError as e:
             # show qt error
             QMessageBox.critical(self, "LED script error", str(e))
             return
+        self.led_script_updated()
+
+    def led_script_updated(self):
+        # update the measurement led script
+        if self.measurement_is_running():
+            self.command_queue.put(("led_script", self.led_script.copy()))
         self.w_led_script.set_script(self.led_script)
+        # update gui
+        self.w_led_script.update_time_predictions()
 
     def app_exit(self) -> None:
         """
diff --git a/cpdctrl_gui/ui/widgets/settings/app_settings.py b/cpdctrl_gui/ui/widgets/settings/app_settings.py
index b503d96..d1a3743 100644
--- a/cpdctrl_gui/ui/widgets/settings/app_settings.py
+++ b/cpdctrl_gui/ui/widgets/settings/app_settings.py
@@ -19,4 +19,5 @@ class AppSettings(QWidget):
         w_plot_n.setMaximum(200000)
         w_plot_n.setSingleStep(1000)
         self.w_form.add_form_row("plot_max_data_points", "Max datapoints in the plot", 20000, w_plot_n, "Maximum number of datapoints in the live plot.\nThis value is limited to ensure performance is not degraded in long measurements")
+        self.w_form.add_form_row("led_script_watch_file", "Watch Led Script File", False, QCheckBox(), "Watch the LED script file for changes and reload it automatically")