diff --git a/examples/mwe.py b/examples/mwe.py
index 86ae8d5..d3c8848 100644
--- a/examples/mwe.py
+++ b/examples/mwe.py
@@ -4,6 +4,7 @@
 
 gaps = fbn.fixbikenet(
     city_name="Frederiksberg municipality",
+    export_file_format="geojson",
 )
 
 # data is saved in current working directory, as gaps.gpkg
\ No newline at end of file
diff --git a/fixbikenet/fixbikenet.py b/fixbikenet/fixbikenet.py
index 8173cce..f17874d 100644
--- a/fixbikenet/fixbikenet.py
+++ b/fixbikenet/fixbikenet.py
@@ -90,11 +90,11 @@ def fixbikenet(
     g = map_edges_to_bike_infrastructure(g)
     edges_gdf = bike_infra_mapping_gdf(g, edges_gdf)
 
-    print("Checking for parallel edges to drop...")
+    print("Dropping parallel edges..")
     edges_to_drop = find_edges_to_drop(g)
     g.remove_edges_from(edges_to_drop)
-    print("Edges dropped")
 
+    print("Detecting gaps..")
     # Capital-G: the Graph() object we will be working with from now on
     G = nx.Graph(g)
 
@@ -111,9 +111,10 @@ def fixbikenet(
     found_gaps, found_gaps_nsp = find_actual_gaps(G, potential_gaps)
 
     # calculating local betweenness score dependent on radius
-    print("Calculating local betweenness centrality..")
+    print("Calculating betweenness centrality..")
     ebc = compute_local_betweenness_centrality(G, nodes_gdf, radius)
 
+    print("Ranking gaps..")
     # calculate parameter B for all gaps, used for deciding which gaps are most important
     Bs = rank_gaps_by_b(found_gaps_nsp, G, ebc)
 
@@ -147,7 +148,7 @@ def fixbikenet(
     if export_data:
         os.makedirs("./results/", exist_ok=True)
         export_data_filename = (
-                city_name + "-" + export_file_format
+                city_name + "." + export_file_format
         )
 
     if export_data:
diff --git a/fixbikenet/functions.py b/fixbikenet/functions.py
index 4f666a7..1345cf0 100644
--- a/fixbikenet/functions.py
+++ b/fixbikenet/functions.py
@@ -312,8 +312,9 @@ def get_correct_edgetuples(edge_gdf, nodelist):
     """
     edgelist_prelim = zip(nodelist, nodelist[1:])
     edgelist_final = []
+    temp_gdf = edge_gdf.sort_index() # To circumvent PerformanceWarning, see https://stackoverflow.com/questions/54307300/what-causes-indexing-past-lexsort-depth-warning-in-pandas
     for edge_prelim in edgelist_prelim:
-        if edge_prelim in edge_gdf.index:
+        if edge_prelim in temp_gdf.index:
             edgelist_final.append(edge_prelim)
         else:
             edgelist_final.append(tuple([edge_prelim[1], edge_prelim[0]]))