diff --git a/omc3_gui/segment_by_segment/measurement_model.py b/omc3_gui/segment_by_segment/measurement_model.py
index 96ec8f2..4a8291d 100644
--- a/omc3_gui/segment_by_segment/measurement_model.py
+++ b/omc3_gui/segment_by_segment/measurement_model.py
@@ -25,9 +25,9 @@ class OpticsMeasurement:
     model_dir: Path =       metafield("Model",              "Path to the model folder",        default=None)
     accel: str =            metafield("Accelerator",        "Name of the accelerator",         default=None)
     output_dir: Path =      metafield("Output",             "Path to the sbs-output folder",   default=None) 
-    year: str =             metafield("Year",               "Year of the measurement (model)", default=None)
-    ring: int =             metafield("Ring",               "Ring of the accelerator",         default=None)
-    beam: int =             metafield("Beam",               "Beam of the accelerator",         default=None) 
+    year: str =             metafield("Year",               "Year of the measurement (model)", default=None, choices=LHC_MODEL_YEARS)
+    ring: int =             metafield("Ring",               "Ring of the accelerator",         default=None, choices=(1, 2, 3, 4))
+    beam: int =             metafield("Beam",               "Beam of the accelerator",         default=None, choices=(1, 2)) 
     elements: Dict[str, Segment] = None  # List of elements
     segments: Dict[str, Segment] = None  # List of segments
 
diff --git a/omc3_gui/segment_by_segment/measurement_view.py b/omc3_gui/segment_by_segment/measurement_view.py
index 5d8a8be..73cf1c3 100644
--- a/omc3_gui/segment_by_segment/measurement_view.py
+++ b/omc3_gui/segment_by_segment/measurement_view.py
@@ -31,8 +31,8 @@ def __init__(self, parent=None, optics_measurement: OpticsMeasurement = None):
         self._update_ui()
 
     def _set_size(self, width: int = -1, height: int = -1):
-        # Set position to the center of the parent
-        parent = self.parent()
+        # Set position to the center of the parent (does not work in WSL for me, jdilly 2023)
+        # parent = self.parent()
         # if parent is not None:
         #     parent_geo = parent.geometry()
         #     parent_pos = parent.mapToGlobal(parent.pos())  # multiscreen support
@@ -61,7 +61,7 @@ def _build_gui(self):
         self._dataclass_ui = DataClassUI.build_dataclass_ui(
             field_def=[
                 FieldUIDef(name="measurement_dir", editable=False), 
-                *(FieldUIDef(name) for name in ("output_dir", "accel", "beam", "year", "ring"))
+                *(FieldUIDef(name) for name in ("model_dir", "output_dir", "accel", "beam", "year", "ring"))
             ],
             dclass=OpticsMeasurement,
         )
@@ -79,6 +79,12 @@ def _update_ui(self):
         self._dataclass_ui.reset_labels()
 
     def accept(self):
+        try:
+            self._dataclass_ui.check_choices(only_modified=True)
+        except ValueError as e:
+            QtWidgets.QMessageBox.critical(self, "Error", str(e))
+            return
+
         self._dataclass_ui.update_model()
         super().accept() 
 
diff --git a/omc3_gui/utils/dataclass_ui.py b/omc3_gui/utils/dataclass_ui.py
index 61df357..26fce5d 100644
--- a/omc3_gui/utils/dataclass_ui.py
+++ b/omc3_gui/utils/dataclass_ui.py
@@ -1,9 +1,16 @@
+""" 
+DataClass UI
+------------
+
+This module allows to generate a simple UI's for dataclasses,
+which allows to edit the values of a dataclass.
+"""
 from functools import partial
 import inspect
 import re
 from dataclasses import MISSING, Field, dataclass, field, fields
 from pathlib import Path
-from typing import Callable, Dict, Optional, Sequence, Tuple, Union
+from typing import Callable, Dict, List, Optional, Sequence, Tuple, Union
 from omc3_gui.utils import file_dialogs
 
 from qtpy import QtWidgets
@@ -151,6 +158,25 @@ def update_model(self):
         for name in self.fields.keys():
             self.update_model_from_widget(name)
 
+    def check_choices(self, only_modified: bool = False):
+        """ Checks all edit-widgets for valid choices. """
+        fields_choices = []
+        for name in self.fields.keys():
+            field = self.model.__dataclass_fields__[name]
+            field_ui = self.fields[field.name]
+            if only_modified and not field_ui.modified:
+                continue
+            
+            choices = field.metadata.get("choices")
+            if choices is not None:
+                value = self.fields[field.name].get_value()
+                if value not in choices:
+                    fields_choices.append(f"{field_ui.label.text()}: {value} not in {choices}")
+
+        if fields_choices:
+            full_str = "\n".join(fields_choices)
+            raise ValueError(f'The following fields contain wrong values:\n{full_str}')
+
     @classmethod
     def build_dataclass_ui(cls, 
         field_def: Sequence[Union[FieldUIDef, str]], dclass: Union[type, object] = None) -> 'DataClassUI':
@@ -243,10 +269,11 @@ def build_dataclass_ui(cls,
 # Type-to-Widget Helpers ----------------------------------------------------------------
 
 class QFullIntSpinBox(QtWidgets.QSpinBox):
+    """ Like a QSpinBox, but overwriting default range(0,100) with maximum integer range. """
 
     def __init__(self, parent: Optional[QtWidgets.QWidget] = None) -> None:
         super().__init__(parent)
-        self.setRange(-2**31, 2**31 - 1)
+        self.setRange(-2**31, 2**31 - 1)  # range of signed 32-bit integers 
 
 
 TYPE_TO_WIDGET_MAP = {