diff --git a/icon_48x48.ico b/icon_48x48.ico
new file mode 100644
index 0000000..d761214
Binary files /dev/null and b/icon_48x48.ico differ
diff --git a/src/NanoVNASaver/Controls/Control.py b/src/NanoVNASaver/Controls/Control.py
index 6ab4e85..43275e8 100644
--- a/src/NanoVNASaver/Controls/Control.py
+++ b/src/NanoVNASaver/Controls/Control.py
@@ -29,6 +29,6 @@ class Control(QtWidgets.QGroupBox):
     def __init__(self, app: QtWidgets.QWidget, title: str = ""):
         super().__init__()
         self.app = app
-        self.setMaximumWidth(240)
+        self.setMaximumWidth(250)
         self.setTitle(title)
         self.layout = QtWidgets.QFormLayout(self)
diff --git a/src/NanoVNASaver/Controls/MarkerControl.py b/src/NanoVNASaver/Controls/MarkerControl.py
index 1282e02..6cb6b21 100644
--- a/src/NanoVNASaver/Controls/MarkerControl.py
+++ b/src/NanoVNASaver/Controls/MarkerControl.py
@@ -55,7 +55,7 @@ class MarkerControl(Control):
         self.check_delta = QCheckBox("Enable Delta Marker")
         self.check_delta.toggled.connect(self.toggle_delta)
 
-        self.check_delta_reference = QCheckBox("reference")
+        self.check_delta_reference = QCheckBox("Reference")
         self.check_delta_reference.toggled.connect(self.toggle_delta_reference)
 
         layout2 = QtWidgets.QHBoxLayout()
diff --git a/src/NanoVNASaver/NanoVNASaver.py b/src/NanoVNASaver/NanoVNASaver.py
index 993c829..a3d3a6e 100644
--- a/src/NanoVNASaver/NanoVNASaver.py
+++ b/src/NanoVNASaver/NanoVNASaver.py
@@ -373,7 +373,6 @@ class NanoVNASaver(QWidget):
         tdr_control_box.setTitle("TDR")
         tdr_control_layout = QtWidgets.QFormLayout()
         tdr_control_box.setLayout(tdr_control_layout)
-        tdr_control_box.setMaximumWidth(240)
 
         self.tdr_result_label = QtWidgets.QLabel()
         self.tdr_result_label.setMinimumHeight(20)
@@ -407,7 +406,6 @@ class NanoVNASaver(QWidget):
         ###############################################################
 
         reference_control_box = QtWidgets.QGroupBox()
-        reference_control_box.setMaximumWidth(240)
         reference_control_box.setTitle("Reference sweep")
         reference_control_layout = QtWidgets.QFormLayout(reference_control_box)
 
@@ -447,18 +445,15 @@ class NanoVNASaver(QWidget):
 
         btn_display_setup = QtWidgets.QPushButton("Display setup ...")
         btn_display_setup.setMinimumHeight(20)
-        btn_display_setup.setMaximumWidth(240)
         btn_display_setup.clicked.connect(lambda: self.display_window("setup"))
 
         btn_about = QtWidgets.QPushButton("About ...")
         btn_about.setMinimumHeight(20)
-        btn_about.setMaximumWidth(240)
 
         btn_about.clicked.connect(lambda: self.display_window("about"))
 
-        btn_open_file_window = QtWidgets.QPushButton("Files")
+        btn_open_file_window = QtWidgets.QPushButton("Files ...")
         btn_open_file_window.setMinimumHeight(20)
-        btn_open_file_window.setMaximumWidth(240)
 
         btn_open_file_window.clicked.connect(
             lambda: self.display_window("file")
diff --git a/src/NanoVNASaver/Windows/CalibrationSettings.py b/src/NanoVNASaver/Windows/CalibrationSettings.py
index 95e0cd2..9f66a7b 100644
--- a/src/NanoVNASaver/Windows/CalibrationSettings.py
+++ b/src/NanoVNASaver/Windows/CalibrationSettings.py
@@ -271,14 +271,14 @@ class CalibrationWindow(QtWidgets.QWidget):
                 self,
                 "Are you sure?",
                 (
-                    "Use of the manual calibration buttons is non-intuitive,"
+                    "Use of the manual calibration buttons is non-intuitive"
                     " and primarily suited for users with very specialized"
-                    " needs. The buttons do not sweep for you, nor do"
+                    " needs. The buttons do not sweep for you nor do"
                     " they interact with the NanoVNA calibration.\n\n"
                     "If you are trying to do a calibration of the NanoVNA, do"
-                    "so on the device itself instead. If you are trying to do"
-                    "a calibration with NanoVNA-Saver, use the Calibration"
-                    "Assistant if possible.\n\n"
+                    " so on the device itself instead. If you are trying to do"
+                    ' a calibration with NanoVNA-Saver, use the "Calibration'
+                    ' assistant" if possible.\n\n'
                     "If you are certain you know what you are doing, click"
                     " Yes."
                 ),
@@ -580,7 +580,7 @@ class CalibrationWindow(QtWidgets.QWidget):
             cal_element.open_c3 = (
                 getFloatValue(self.open_c3_input.text()) / 1.0e45
             )
-            cal_element.openLength = (
+            cal_element.open_length = (
                 getFloatValue(self.open_length.text()) / 1.0e12
             )
 
@@ -711,16 +711,16 @@ class CalibrationWindow(QtWidgets.QWidget):
             "Calibration assistant",
             (
                 "This calibration assistant will help you create a calibration"
-                " in the NanoVNASaver application.  It will sweep the"
-                "standards for you, and guide you through the process.<br><br>"
+                " in the NanoVNASaver application. It will sweep the"
+                " standards for you and guide you through the process.<br><br>"
                 "Before starting, ensure you have Open, Short and Load"
-                " standards available, and the cables you wish to have"
-                " calibrated with the device connected.<br><br>"
+                " standards available and the cables you wish to have"
+                " calibrated connected to the device.<br><br>"
                 'If you want a 2-port calibration, also have a "through"'
-                " connector to hand.<br><br>"
+                " connector on hand.<br><br>"
                 "<b>The best results are achieved by having the NanoVNA"
-                " calibrated on-device for the full span of interest and saved"
-                " to save slot 0 before starting.</b><br><br>"
+                " calibrated on-device for the full span of interest and stored"
+                " in save slot 0 before starting.</b><br><br>"
                 "Once you are ready to proceed, press Ok."
             ),
             QtWidgets.QMessageBox.StandardButton.Ok | QtWidgets.QMessageBox.StandardButton.Cancel,
@@ -932,7 +932,7 @@ class CalibrationWindow(QtWidgets.QWidget):
                 QtWidgets.QMessageBox.Icon.Information,
                 "Calibrate complete",
                 (
-                    "The calibration process is now complete.  Press"
+                    "The calibration process is now complete. Press"
                     ' "Apply" to apply the calibration parameters.'
                 ),
                 QtWidgets.QMessageBox.StandardButton.Apply | QtWidgets.QMessageBox.StandardButton.Cancel,