diff --git a/allowed.mac b/allowed.mac
index 5aba4c8f083dd17aa84bd67dd0610db8cb79e402..d6f64e9d6a5856a56f5a844392654be7fc05cfd9 100644
--- a/allowed.mac
+++ b/allowed.mac
@@ -4,7 +4,6 @@
 
 # magnetic field strength
 /VK/field/maxbfield 0.48 tesla
-/VK/detector/volumes/blinkers true
 
 # source dimensions
 /VK/source/diskShapedSource true
diff --git a/compile.sh b/compile.sh
index 7b3184d2d76e36b9a742ba36f6172c083bc92463..6ec778b04fc84cd7cc27949b073ebef50151f265 100755
--- a/compile.sh
+++ b/compile.sh
@@ -1,6 +1,6 @@
 rm -f CMakeCache.txt
 rm -rf CMakeFiles
-cmake -DCMAKE_BUILD_TYPE=DEBUG -DGeant4_DIR=/home/oliskir/src/geant-4.10/geant4.10.3-install/lib/Geant4-10.3.0 $pwd
-#cmake -DCMAKE_BUILD_TYPE=DEBUG -DGeant4_DIR=/home/oliskir/src/geant4/geant4.10.2-install/lib/Geant4-10.2.0 $pwd -DCMAKE_BUILD_TYPE=DEBUG
+#cmake -DCMAKE_BUILD_TYPE=DEBUG -DGeant4_DIR=/home/oliskir/src/geant-4.10/geant4.10.3-install/lib/Geant4-10.3.0 $pwd
+cmake -DCMAKE_BUILD_TYPE=DEBUG -DGeant4_DIR=/home/oliskir/src/geant4/geant4.10.2-install/lib/Geant4-10.2.0 $pwd -DCMAKE_BUILD_TYPE=DEBUG
 make -j4
 
diff --git a/electron.mac b/electron.mac
index 58cbea7b5229ff96819ef031ab4c5a9d0231ce28..ab02b4805569fe067d2a1571a0108dd72af04cf1 100644
--- a/electron.mac
+++ b/electron.mac
@@ -5,9 +5,6 @@
 /VK/output/zeroSuppression true
 /VK/storeTrajectoryData true
 
-# magnetic field
-/VK/field/maxbfield 0.145 tesla
-
 # source dimensions
 /VK/source/diskShapedSource true
 /VK/source/innerDiameter 0 cm
@@ -21,6 +18,9 @@
 
 #/gps/energy 975.657 keV
 /gps/energy 1682.232 keV
-/VK/output/openFile output/electron.root                
-/run/beamOn 100000
 
+# magnetic field
+/VK/field/maxbfield 0.145 tesla
+
+/VK/output/openFile output/electron.root                
+/run/beamOn 10000
diff --git a/init.mac b/init.mac
index c306c1da12de7ca1a2f162d60023725d5c6d11a6..be4e23e30b7d1dbc0fd15d8112fac7a4819350c9 100644
--- a/init.mac
+++ b/init.mac
@@ -13,6 +13,7 @@
 /VK/detector/volumes/magnet true
 /VK/detector/volumes/catcherFoil true
 /VK/detector/volumes/shield true
+/VK/detector/volumes/blinkers true
 /VK/storeTrajectoryData false
 
 # field
diff --git a/src/VKPhysicsList.cpp b/src/VKPhysicsList.cpp
index f2260eeb262573981484115bdfef761b3576a679..2c54d6c7f8657aad873ea56cf8e48199f01a2e84 100644
--- a/src/VKPhysicsList.cpp
+++ b/src/VKPhysicsList.cpp
@@ -56,8 +56,10 @@ VKPhysicsList::VKPhysicsList()
 
     // EM Physics
     RegisterPhysics(new VKEMPhysics("standard EM"));
+    // RegisterPhysics(new G4EmStandardPhysics_option4()); // not yet tested
     // RegisterPhysics(new G4EmLivermorePhysics());  // overpredicts muon energy loss by a factor of 2!
     // RegisterPhysics(new G4EmLowEPPhysics());
+    // RegisterPhysics(new G4EmPenelopePhysics()); // not yet tested
     
     // Muon Physics
     RegisterPhysics(new VKMuonPhysics("muon"));
diff --git a/src/VKScintillatorSensitiveDetector.cpp b/src/VKScintillatorSensitiveDetector.cpp
index 880fe632e9686ff023beaa0c145a5fdc838b3e57..44e166209c0abd351c9d3d61df686f931c27c457 100644
--- a/src/VKScintillatorSensitiveDetector.cpp
+++ b/src/VKScintillatorSensitiveDetector.cpp
@@ -59,7 +59,7 @@ void VKScintillatorSensitiveDetector::Initialize(G4HCofThisEvent* hitsCE)
     // A way to keep all the hits of this event in one place if needed
     static G4int hitsCID = -1;
     if (hitsCID<0) {
-        hitsCID = GetCollectionID(0);
+        hitsCID = GetCollectionID(0);  // "CID" = Collection ID
     }
     hitsCE -> AddHitsCollection(hitsCID, fScintCollection);
 }
@@ -89,6 +89,7 @@ G4bool VKScintillatorSensitiveDetector::ProcessHits(G4Step* aStep,G4TouchableHis
     scintHit -> SetEdep(edep);
     scintHit -> SetPos(pos);
 
+    // Add hit to collection
     fScintCollection->insert(scintHit);
 
     return true;