diff --git a/src/viewer/pages/plot_sMRI_vars_study.py b/src/viewer/pages/plot_sMRI_vars_study.py
index adffbdd..3c321bb 100644
--- a/src/viewer/pages/plot_sMRI_vars_study.py
+++ b/src/viewer/pages/plot_sMRI_vars_study.py
@@ -88,6 +88,8 @@ def panel_incsv() -> None:
                 st.session_state.paths["file_search_dir"],
             )
 
+        print(f'aaaa {st.session_state.is_updated["csv_plot"]}')
+
         if os.path.exists(st.session_state.paths["csv_plot"]):
             p_plot = st.session_state.paths["csv_plot"]
             st.success(f"Data is ready ({p_plot})", icon=":material/thumb_up:")
@@ -103,6 +105,7 @@ def panel_incsv() -> None:
             st.session_state.is_updated["csv_plot"] = False
 
             # Show input data
+        if os.path.exists(st.session_state.paths["csv_plot"]):
             with st.expander('Show input data', expanded=False):
                 st.dataframe(st.session_state.plot_var["df_data"])
 
@@ -188,6 +191,10 @@ def panel_select() -> None:
 
         df = st.session_state.plot_var["df_data"]
 
+        if 'MRID' not in df.columns:
+            st.warning('The data file does not contain the required "MRID" column. The operation cannot proceed.')
+            return
+
         with open(st.session_state.dict_categories, "r") as f:
             dict_categories = json.load(f)
 
@@ -247,11 +254,13 @@ def panel_select() -> None:
             sel_vars = sel_vars + vars_cent
             st.session_state.plot_sel_vars = sel_vars
             
-            print(f'sss {vars_cent}   nnnn {sel_vars}')
-                        
             df = df[st.session_state.plot_sel_vars]
             st.session_state.plot_var["df_data"] = df
 
+            with st.expander('Show selected data', expanded=False):
+                st.dataframe(st.session_state.plot_var["df_data"])
+
+
         col1, col2 = st.columns([0.5, 0.1])
         with col2:
             if st.button("Revert to initial data", use_container_width=True):
diff --git a/src/viewer/utils/utils_st.py b/src/viewer/utils/utils_st.py
index c9400a7..c7d7a59 100644
--- a/src/viewer/utils/utils_st.py
+++ b/src/viewer/utils/utils_st.py
@@ -268,7 +268,6 @@ def util_panel_workingdir(app_type: str) -> None:
         utilses.update_default_paths()
         utilses.reset_flags()
 
-
 def copy_uploaded_to_dir() -> None:
     # Copies files to local storage
     if len(st.session_state["uploaded_input"]) > 0:
@@ -312,11 +311,6 @@ def util_upload_file(
     Upload user data to target folder
     Input data is a single file
     """
-    # Set target path
-    if not flag_disabled:
-        if not os.path.exists(os.path.dirname(out_file)):
-            os.makedirs(os.path.dirname(out_file))
-
     # Upload input
     in_file = st.file_uploader(
         title_txt,
@@ -325,14 +319,18 @@ def util_upload_file(
         disabled=flag_disabled,
         label_visibility=label_visibility,
     )
+    if in_file is None:
+        return False
 
-    # Copy to target
-    if not os.path.exists(out_file):
-        utilio.copy_uploaded_file(in_file, out_file)
-        return True
-
-    return False
-
+    # Create parent dir of out file
+    if not os.path.exists(os.path.dirname(out_file)):
+        os.makedirs(os.path.dirname(out_file))
+    # Remove existing output file
+    if os.path.exists(out_file):
+        os.remove(out_file)
+    # Copy selected input file to destination
+    utilio.copy_uploaded_file(in_file, out_file)
+    return True
 
 def util_select_folder(
     key_selector: str,